Full text of "The secret of everyday things; informal talks with the children"

See other formats

Sf5S*s*i«B"tLyxFTRaJ.^Efasrt*.

il(LJ)i»

\ro

/^/1'fe^c=.g4'

-d

J/ir^^")

vvi—

BOSTON
PUBLIC
LIBRARY

MtRRlC' ^' •'il!C LIB.

APK.

1^0

JAN 4

APR ^'
AUG 2 7 ' „L

OCT 25 j'

JUNI? MA?/

l"*;-!

L f3 APR 2.0

<Jb

OCT 15

?£pf&

-)<*

p-jUi

THE SECRET

EVERYDAY THINGS

THE SECRET

EVERYDAY THINGS

INFORMAL TALKS WITH THE CHILDREN

1 J

) ?)^3&

JEAN -HENRY FABRE

Author of "The Story-Book of Science,'
"Our Humble Helpers," "Field,
Forest and Farm," etc.

TRANSLATED FROM THE FRENCH
BY

FLORENCE CONSTABLE BICKNELL

.e^v*^

NEW YORK

THE CENTURY CO,

1920

INTKODUCTORY NOTE

The clearness, simplicity, and charm of the great
French naturalist ^s style are nowhere better illus-
trated than in this work, which in its variety of sub-
ject-matter and apt use of entertaining anecdote
rivals **The Story-Book of Science,'* already a
favorite with his readers. Such instances of an-
tiquated usage or superseded methods as occur in
these chapters of popular science easily win our in-
dulgence because of the literary charm and warm hu-
man quality investing all that the author has to say.
— Translator,

CONTENTS

CHAPTER PAGE

I Thread 3

II Pins 8

III Needles 13

lY Silk 20

V Wool 25

VI Flax and Hemp 31

VII Weaving 37

VIII Woolen Cloth 41

IX Moths 47

X Napery 53

XI Calico 59

XII Dyeing and Printing 64

XIII Dyestuffs 71

XIV He.vt- Conduction 77

XV Human Habitations 82

XVI Clothing 87

XVII ASHE&— POTxVSH 92

XVIII Soap 98

XIX Fire . ^ . 104

XX Matches 109

XXI Wood and Charcoal 113

XXII Coal and Coal-Gas 119

XXIII Combustion 124

XXIV Heating . 129

XXV Lighting 136

XXVI Kerosene Oil 141

XXVII Glass . 148

XXVIII Iron 154

XXIX Rust 159

XXX Tin-Plating 162

XXXI Pottery 167

vii

viii CONTENTS

CHAPTER PAGE

XXXII Coffee 172

XXXIII Sugar , , . .^ 180

XXXIV Tea 187

XXXY Chocolate 193

XXXVI Spices -,.-... 198

XXXVII Sai.t 203

XXXVIII Olive Oil 207

XXXIX Double Boiler 213

XL Little Pests 217

XLI Flies . 224

XLII The Three States of Matter . . . 230

XLIII Distillation 236

XLIV Water 242

XLV Water (Continued) 248

XL VI Vinegar 252

XLVII The Grist Mill 257

XLVIII Bread 261

XLIX Other Wheat Products 266

L Strange Uses of Starch 271

LI Rice 276

LII Chestnuts . 279

LIII Codfish 285

LIV Air . 292

LV Air (Continued) 298

LVI Impure Air 304

LVII Germs 312

LVIII The Atmosphere 320

LIX Evaporation 329

LX Humidity in the Atmosphere . . .335

LXI Rain 340

LXII Snow 344

LXIII Ice 350

LXIV Pebbles 354

LXV The Force of Steam 359

LXVI Sound 365

LXVII Sound (Continued) 370

LXVIII Light 376

THE SECRET OF
EVERYDAY THINGS

#11

THE SECRET OF
EVERYDAY THINGS

CHAPTER I

THREAD

UNCLE PAUL resumed his talks on things that
grow and things that are made, while his
nephews, Jules and Emile, and his nieces, Claire and
Marie, listened to his **true stories,'' as they liked
to call them, and from time to time asked him a
question or put in some word of their own.

Continuing the subject of cotton-manufacture, he
called his hearers' attention to the number of pro-
cesses the raw material must go through before it
emerges as finished fabric ready for making into
wearing apparel, and to the countless workmen that
must, from first to last, have been engasred in its pro-
duction and in all the operations leading up to its
final application to household uses.

*^Then I should think," said Marie, *^that cotton
cloth would be very expensive if all those workmen
are to get their pay for the time and labor they have
put into its manufacture."

**0n the contrary," Uncle Paul assured her, **the
price is kept down to a very moderate figure ; but to
accomplish this surprising result two powerful fac-
tors are called into play, — wholesale manufacture

THE SECRET OF EVERYDAY THINGS

and the use of machinery. The process employed
for spinning cotton into the thread that you see
wound on spools will help you to understand my
meaning.

".You know how the housewife spins the tow that

is used for making linen.
First she thrusts inside
her belt the distaff, made
out of a reed and bearing
at its forked end a bunch
of tow ; then with one hand
she draws out the fibers
and gathers them together
by moistening them a little
with her lips, while with
the other she twirls her
spindle and thus twists the
loose fibers into a single strand. After she has
twisted it tightly enough she winds it on the spindle,
and then proceeds to draw out another length of
tow from the distaff."

''Mother Annette is very skilful with the distaff,'^
put in Claire. ''I like to hear her thumb snap when
she twirls the spindle. But when she spins wool she
uses a spinning-wheel."

' ' First of all, ' ' Uncle Paul explained, ' ' the carded
wool is divided into long wisps or locks. One of
these is brought into contact with a rapidly twirling
hook, which catches the wool and twists it into a
thread that lengthens little by little at the expense
of the lock of wool, the latter being all the while held
and controlled by the fingers. When the thread has

Spinning-Wheel for Flax

a, bench or stool; h, stand-
ards ; c, driving band-wheel with
grooved rim ; d, treadle ; e, rod
connecting treadle with crank ; /,
cord-band driving the flier-spin-
dle ; g, flier ; h, distaff carrying
flax to be spun and, when in use,
held in operator's left hand.

THREAD 5

attained a certain length it is wound on the spindle
by a suitable movement of the wheel; and then the
twisting of the lock of wool is resumed. In case of
need cotton could be thus spun by hand ; but, skilful
as Mother Annette is at such work, cloth made from
thread spun in that fashion would be enormously
expensive because of the time spent in producing it.
What, then, shall we do! We must resort to ma-
chinery, and in vast establishments known as cotton
factories we set up hundreds of thousands of spindles
and bobbins, all moving with perfect precision and
so rapidly that the eye cannot follow them. ' '

^*It must be wonderful,'^ remarked Jules, ^*to see
all those machines spinning the cotton into thread
so fast you can 't keep track of them. ' ^

*'Yes, those machines, surpassing in delicate dex-
terity the nimble fingers
of the most skilful spin-
ner, are indeed among
the cleverest inventions
ever produced by man;
but they are so compli-
cated that the eye gets

lost amoTiP- tbpir n'rinn Spinning-Wheel for Wool

lOSI among ineir mnU- „ bench; h, V, standards; c.

■..^^^^^'U^r^ -^^^i^ T driving band-wheel with flat rim,

meraDle parts. l can turned by the pe? k held in the right
, . hand of the spinner; d. cord band,

only point out to you the crossed at e and driving the speed-
pulley /; g, cord-band imparting mo-

more important of these ^^IJ^^ ^^\ltl\u^. ''' '' '^'''^^ '"^
parts, without hoping to make you understand how
the whole machine operates.

** First there are the cards which comb the mass of
cotton into tine strips or ribbons, just as Mother
Annette cards the wool she is about to spin on her

THE SECRET OF EVERYDAY THINGS

wheel. These cards of hers, you understand, are
nothing more nor less than big brushes bristling with
a multitude of fine iron points. One card remains
at rest and receives a thin layer of wool, after which
the other is made to pass over it in such a way as to
comb the wool and draw out fine locks of it, one after
another. In this fashion, too, the cards in cotton
factories play their part. On leaving the cards the
ribbons of cotton fiber are drawn out, lightly twisted,
and then wound on bobbins. Next a machine called

^/ a spinning - jenny
, takes the partly spun
cotton and twists it
into thread more or
less fine according to
the purpose it is to
serve. Finally this

Hargreaves's Original Spinning-Jenny thread finds its Way

a, frame; b, frames supporting spindles; . x' n x xi

c, drum driven by the band e from the automatically tO 1116
band-Avheel /, and carrying separate bands , .

(not shown) which separately drive each rggl wllich formS it
spindle; d. fluted wooden clasp which trav- ^

els on wheels on the top of the frame, and iyrf/^ olraina nf irk iVio

in which the rovings (the slightly twisted A^^LU blVfilito, Ui tU LlltJ
fibers) are arranged in due order. • t i • i • j

Winder, which winds
it into those regular balls that we can't admire too
much for their perfect shape. You have doubtless
observed with what precision, what elegance, the
thread is wound into a ball that the merchant de-
livers to you at the insignificant price of a few cen-
times. What human hands would have the steadi-
ness, what fingers the skill to achieve anything com-
parable with this little masterpiece f

**I know I can't begin to wind such a ball/^ said

THREAD 7

Marie; ^4t just makes a shapeless lump instead of
the pretty ball I buy at the store. ' '

^^No one, depending only on his hands, could ever
achieve that admirable regularity,'^ Uncle Paul as-
sured her. **To that end we must have machines,
unvarying in their movements and working with a
precision that nothing can derange.

^'Thread is numbered according to its degree of
fineness, the higher the number the finer the thread.
Every skein and every ball being of the same length,
its weight increases as the fineness diminishes. We
say, then, of a particular thread that it is number
200 when it takes two hundred skeins or balls to
make half a kilogram in weight, and that it is num-
ber 150 when it takes one hundred and fifty to make
up the same weight. ' '

CHAPTER n

PINS

a A pTER thread, come the needle and its com-

panion the pin. I shall take up the latter first,
because its manufacture will help us to understand
that of the needle, which is rather more complicated.

^*The things most often used by us are not seldom
those of whose origin we are ignorant. What is
there more convenient, more often used, than the
needle and the pin? What could take their place if
we were deprived of them? We should be reduced
to Claire's makeshift that day we went on a picnic
and she tore a hole in her apron and fastened the
edges together with a thorn from the hedge. We
might also, as do those savage tribes that have no
manufactured articles, shred an animal sinew or a
strip of bark into fine thongs to serve as thread and
sew with a sharp-pointed bone for a needle. We
might replace the pin by a fish bone."

^^That would be a funny sort of gown,'' exclaimed
Marie, ^ ' sewed with thongs of bark or the sinews of
an ox ; nor should I care much to have my hair fast-
ened with codfish bones."

^^ Yet there are even to-day savage tribes that have
nothing else; and often the great ladies of ancient
times had nothing better : they used rude pins made
of metal or little splinters of bone. Advance in the

PINS 9

manufacturing arts has given us the pin, with its
pretty round head, at a price so moderate as to be
almost negligible, the needle with its fine point and
its admirable suitability to our use, and thread of
remarkable strength and fineness. Now let us learn
how pins are made.

'^Pins are made of brass, which is composed of
copper and zinc. Copper is the red metal you are
familiar with in copper kettles, zinc the grayish-
white metal of watering-pots and bath-tubs. Mixed
together they form brass, which is yellow.

^^The first step is to reduce the copper to wire the
size of a pin. This is done by means of a draw-plate,
a steel plaque pierced with a series of holes, each
smaller than the preceding.* A little brass rod is
thrust into the largest hole and forcibly drawn
through it. In passing through this hole, which is
a little too small for it, the metal rod becomes cor-
respondingly thinner and longer. It is then thrust
into a still smaller hole and again drawn out, becom-
ing once more thinner and longer in the process.
This operation is continued, passing from one liole
of the draw-plate to the next smaller, until the wire
acquires the deisired fineness.

*^ While we are on the subject note this fact — that
all metal wires, whether of iron, copper, gold, or sil-
ver, are made in the same way: namely, by being
passed through the draw-plate.

^^The brass wires are now put into the hands of
the cutter, who gathers several of them into a bundle
and then, with a strong pair of shears, cuts them all
into pieces twice the length of a pin.

10 THE SECRET OF EVERYDAY THINGS

^^ These pieces must next be sharpened at both ends
by means of a steel grindstone which has its grind-
ing-surface furrowed like a file, and which turns with
the prodigious velocity of twenty-seven leagues an
hour. The man charged with this work, whom we
will call the sharpener, sits on the ground in front
of his grindstone, legs crossed in tailor-fashion. He
takes in his fingers from twenty to forty pieces,
spreads them out regularly in the shape of a fan, and
brings all these branching tip-ends simultaneously
into contact with the grindstone, at the same time
twirling them in his fingers so that the tip is worn
off equally all around and the point made even. The
reverse tips are sharpened in the same way.

^'But this first process merely produces points in
the rough, so to speak ; the sharpener retouches and
finishes them on a finer grindstone. Finally the
pieces sharpened at both ends are arranged several
together and cut in two in the middle with one clip
of a pair of shears. Each half, known as a shank,
now lacks only a head in order to become a complete
pin.

**This heading process is the most difficult part of
the whole operation. On a slender metal shaft, very
smooth and slightly larger than the pins, a thread of
brass is tightly wound in a spiral, after which the
shaft is removed, leaving a long corkscrew with its
turns touching one another. A cutter of consum-
mate skill in this delicate work, which demands at
the same time so much precision and so much swift-
ness, divides this corkscrew into small pieces, each

PINS 11

containing just two turns. Each of these pieces is
a head.

'^The workman who is to put them in place and
fasten them takes the shanks one by one and plunges
them haphazard, pointed end first, into a wooden
bowl full of heads. The shank is drawn out with a
head strung on it, which the operator pushes with his
fingers to the unpointed end. He immediately places
it on a little anvil having a tiny cavity into which the
head fits; then by means of a pedal moved by the
operator's foot a hammer provided with a similar
cavity comes down, strikes five or six little blows,
and behold the head firmly fixed.

**As a finishing touch the pins have still to be
coated with tin. To this end they are boiled with a
certain proportion of this metal in a liquid capable
of dissolving it and depositing it in a thin layer on
the brass. After being thus coated they are washed,
dried on cloths, and finally shaken up with bran in a
leather bag in order to heighten their polish.

^^It only remains to stick the pins in paper in regu-
lar rows. A kind of comb with long steel teeth
pierces the paper with two lines of holes. Work-
women knowm' as pin-stickers are charged with the
delicate task of inserting the pins one by one in these
holes. A skilled pin-sticker can insert from forty
to fifty thousand pins a day.

^'Including some details that I omit, the manu-
facture of a pin requires fourteen different opera-
tions, and consequently the cooperation of fourteen
workmen, all of consummate skill in their part of the

12 THE SECRET OF EVERYDAY THINGS

operation. Nevertheless the manufacture is so
rapid that these fourteen workmen can make twelve
thousand pins for the modest sum of four francs." ^

1 Since the foregoing was written automatic machinery has been
invented which greatly facilitates the manufacture of pins. Point-
ing, heading, and papering are now done with great rapidity by
such machinery, and hand-work is almost entirely dispensed with. —
Translator.

CHAPTER III

NEEDLES

TAKE from a case cne of the finest needles, ex-
amine its sharp point, its tiny, almost imper-
ceptible eye, and note finally the polish, the shine.
Tell me if this pretty little tool, so perfect in its
minuteness, would not seem to require for its manu-
facture the superhuman fingers of a fairy rather
than man's heavy hands. Nevertheless it is robust
workmen with knotty fingers blackened by the forge
and covered with great calluses that do this most
delicate work. And how many workers does it take
to make one needle! — one only! For the manu-
facture of a pin, I have already told you, it takes
fourteen different workmen ; for the manufacture of
a needle it requires the cooperation of one hundred
and twenty, each of whom has his special work. And
yet the average price of a needle is about one cen-
time. ^

'^The metal of needles is steel, which is obtained
by adding carbon to iron heated to a very high
temperature. Under this treatment iron changes its
nature a little, incorporating a very small quantity
of carbon and thus becoming exceedingly hard, but
at the same time brittle. A needle must be very
hard in order not to bend under the pressure of the

1 Nearly one fifth of a cent in our money. — Translator.

U THE SECRET OF EVERYDAY THINGS

thimble forcing it through the thickness of the ma-
terial on which the seamstress is at work, and also in
order that the point may not become blunted, but al-
ways retain the same power of penetration. Steel,
the hardest of all the metals, is the only one that ful-
fils these conditions of resistance ; neither copper nor
iron nor the precious metals, gold and silver, could
replace it. A gold needle, for example, in spite of
its intrinsic value, would be useless, becoming
blunted and twisted before using up its first needle-
ful of thread. Steel alone is suited to the manu-
facture of needles, though unfortunately this metal
is brittle, and the more so the harder it is. ' '

**But I should think,'' Marie interposed, *Hhat
since steel is so hard it ought not to break. ' '
n ' I ^ ^ You will think

ff otherwise if you

listen to me a
while. Hardness
is the degree of
resistance that a
body opposes to
being cut, scratch-
^^^^^^^ ed, worn away by

Various shapes and sizes used by sailmakers and

upholsterers. aUOthcr. Of tWO

bodies rubbing against each other the harder is that
which cuts the other, the softer is that which is cut.
Steel, which scratches iron, is harder than iron; in
its turn glass is harder than steel, because it can cut
the steel without being cut by it. But a diamond
is still harder than glass, since it scratches glass
and glass cannot scratch it. In fact, a diamond is

NEEDLES 15

the hardest of all known substances : it scratches all
bodies and is scratched by none. Glaziers take ad-
vantage of this extreme hardness : they cut their
panes of glass with the point of a diamond."

^'I have heard," said Claire, ^Hhat a diamond
placed on an anvil and struck with a hammer stands
the blows without breaking and penetrates into the
iron of the anvil, it is so hard. ' ^

'^That is a great mistake," replied Uncle Paul.
**A diamond breaks like glass, and he would be very
ill-advised who should submit the precious stone to
the proof of the hammer. At the first blow there
would be nothing left but a little worthless dust.
You see by these different examples that hardness
and brittleness are often united. Steel is very hard,
glass still harder, the diamond the hardest of all
substances; nevertheless all three are brittle. That
explains to you why needles of excellent steel, which
gives them their rigidity and power of penetration,
nevertheless break like glass in clumsy fingers.

**Now I come to the subject of manufacture, from
which the properties of steel turned us for a moment.
The metal is drawn out into wire by means of a
draw-plate ; then this wire, several strands at a time,
is cut into pieces twice the length of a needle, just as
in pin-making. The pieces are pointed at each end,
first on a revolving sandstone similar to an ordinary
grindstone, then on a wooden wheel covered with a
thin layer of oil and a very fine, hard powder called
emery. Imagine glass reduced to an impalpable
powder and you will have a sufficiently correct idea
of what emery is. The first process gives a more

16 THE SECRET OF EVERYDAY THINGS

or less coarse point ; the second sharpens this point
with extreme nicety.

' ^ The pieces thus pointed at both ends are cut into
two equal parts, each one of which is to be a needle.
The workman then takes in his fingers four or five
of these unfinished needles, spreads them out like a
fan and puts the large end of them on a little anvil ;
then with a light blow of the hammer he slightly flat-
tens the head of each. It is in this flattened end that
later on the eyelet or hole of the needle will be
pierced. '^

*^But you just told us, Uncle," Marie interrupted,
*'that good steel is brittle, the same as glass; yet
the workman flattens the head of his needles with a
hammer without breaking anything."

^*Your remark is very timely, for before going
further we have to take note of one of the most
curious properties of steel. I must tell you that it
is only by tempering that this metal becomes hard
and at the sraue time brittle. Tempering steel is
heating it red-hot and then cooling it quickly by
plunging it into cold water. Until it undergoes this
operation steel is no harder than iron; but, to com-
pensate for this softness, it can then be hammered,
forged, and in fact worked in all sorts of ways with-
out risk of breaking. Once tempered, it is very
hard and at the same time so brittle that it can never
henceforth stand the blow of a hammer. Accord-
ingly needles are not tempered until near the end of
the process of manufacture; before that they are
neither hard nor brittle and can be worked as easily
as iron itself.

NEEDLES 17

*'If you look at a needle attentively you will see
that the head is not only flattened but also hollowed
out a little on each side in the form of a gutter or
groove which serves to hold the thread. To obtain
this double groove, the workman places the needles,
one by one, between two tiny steel teeth which, moved
by machinery, open and shut like two almost invisi-
ble jaws. Bitten hard by the shutting of these two
teeth, the head of the needle is indented with a groove
on each side.

^'Now the eye must be pierced, an operation of
unequalled delicacy. Two workmen cooperate in
this, each equipped with a steel awl whose fineness
corresponds with the hole to be made. The first
places the head of the needle on a leaden block, puts
the point of his instrument in the groove on one side,
and, striking a blow with the hammer on the jiead
of the awl, thus obtains not a complete hole but
merely a dimple. The needle is then turned over and
receives a similar dimple on the other side. The
other workman takes the needles and with the aid of
his awl removes the tiny bit of steel that separates
the two dimples. Behold the eye completely
finished.

*^ Probably no work requires such sureness of hand
and precision of sight as the piercing of the eye of
a needle. Certainly he has no trembling fingers or
dimmed eyesight who can, without faltering, apply
his steel point to the fine head of a needle, strike with
perfect accuracy the blow of the hammer, and open
the imperceptible orifice that my eyes can scarcely
find when I want to thread a needle. ' ^

18 THE SECRET OF EVERYDAY THINGS

** There are needles so small/' remarked Marie,
**that I really don't see how any one can manage to
make an eye in them.''

*'This incomprehensible achievement is mostly the
work of astonishingly skilful children. So skilful,
indeed, are some of them that they can make a hole
in a hair and pass a second hair through this hole."

*^Then the needle's eye," said Emile, *^ which
seems such a difficult piece of work to us, is only
child's play to them."

^^ Child's play indeed, so quick and dexterous are
they at it. And they have still another kind of dex-
terity that would astonish you no less. To make
the needles easier to handle in the process of manu-
facture, they must be placed so that they all point
the same way ; but as in passing from one operation
to another, from one workman to another, they be-
come more or less disarranged, it is necessary to
arrange them in order again, all the points at one
end, all the heads at the other. For us there would
be no way but to pick them up one by one ; with these
children this delicate task is but the work of an
instant. They take a handful of needles all in dis-
order, shake them in the hollow of the hand, and that
is enough; order is reestablished, the heads are to-
gether, the points together.

*^The eye completed, the next process is tempering,
to give the steel its required hardness. The needles
are arranged on a plate of sheet-iron, which is then
placed on red-hot coals. When sufficiently heated,
the needles are dropped quickly into a bucket of cold
water. This produces in them the hardness charac-

NEEDLES 19

teristic of steel, and its accompanying brittleness.

**As a finishing touch the needles must be polished
till they shine brightly. In parcels of fifteen or
twenty thousand each they are sprinkled with oil and
emery and wrapped up in coarse canvas tied at both
ends. These round packages, these rolls, are placed
side by side on a large table and covered with a
weighted tray. Workmen or machinery then make
the tray pass back and forth over the table unceas-
ingly for a couple of days. By this process the
packages, drawn this way and that by the tray, roll
along the table, and the needles, rubbing against one
another, are polished by the emery with which they
are sprinkled.

*^0n coming out of the polishing machine the
needles, soiled with refuse of oil and detached
particles of steel, are cleaned by washing with hot
w^ater and soap. It only remains now to dry them
well, discard those that the rude operation of polish-
ing has broken, and finally wrap with paper, in pack-
ages of a hundred, those that have no defect. The
most celebrated needles come from England, but
needles are also made in France, at Aigle in the de-
partment of Oriie.'^^

1 Since Fabre wrote, the manufacture of needles, like that of pins,
has undergone important changes and improvements through the ap-
plication of machinery. — Translator.

CHAPTER IV

SILK

THE culture of the silkworm having been ex-
plained by Uncle Paul in one of his previous
talks, ^ he now confined himself chiefly to the struct-
ure of the cocoon and the unwinding of the delicate
silk thread composing it.

*^The cocoon of the silkworm,'^ he began, *^is com-
posed of two envelops : an outer one of very coarse
gauze, and an inner one of very fine fabric. This
latter is the cocoon properly so called, and from it
alone is obtained the silk thread so highly valued in
manufacture and commerce, whereas the other, ow-
ing to its irregular structure, cannot be unwound
and furnishes only an inferior grade of silk suitable
for carding.

^'The outer envelop is fastened by some of its
threads to the little twigs amid which the worm has
taken its position, and forms merely a sort of scaf-
folding or openwork hammock wherein the worm
seeks seclusion and establishes itself for the serious
and delicate task of spinning its inner envelop.
When, accordingly, the hammock is ready the worm
fixes its hind feet in the threads and proceeds to
raise and bend its body, carrying its head from one
side to the other and emitting from its spinneret as
it does so a tiny thread which, by its sticky quality,

1 See "Tlie Story-Book of Science."

SILK 21

immediately adheres to the points touched. With-
out change of position the caterpillar thus lays one
thickness of its web over that portion of the enclos-
ure which it faces. Then it turns to another part
and carpets that in the same manner. After the en-
tire enclosure has thus been lined, other layers are
added, to the number of five or six or even more. In
fact, the process goes on until the store of silk-mak-
ing material is exhausted and the thickness of the
wall is sufficient for the security of the future
chrysalis.

^^From the way the caterpillar works you will see
that the thread of silk is not wound in circles, as it
is in a ball of cotton, but is arranged in a series of
zigzags, back and forth, and to right and left. Yet
in spite of these abrupt changes in direction and
notwithstanding the length of the thread — from three
hundred to five hundred meters — there is never any
break in its continuity. The silkworm gives it forth
uninterruptedly w^ithout suspending for a moment
the work of its spinneret until the cocoon is finished.
This cocoon has an average weight of a decigram and
a half, and it would take only fifteen or twenty kilo-
grams of the silk thread to extend ten thousand
leagues, or once around the earth.

^^ Examined under the microscope, the thread is
seen to be an exceedingly fine tube, flattened and w^ith
an irregular surface, a^d composed of three distinct
concentric layers, of which the innermost one is pure
silk. Over this is laid a varnish that resists the
action of warm water, but dissolves in a weak alka-
line solution. Finally, on the outside there is a

^2 THE SECRET OF EVERYDAY THINGS

gummy coating which serves to bind the zigzag
courses firmly together and thus to make of them a
substantial envelop.

**As soon as the caterpillars have completed their
task, the cocoons are gathered from the sprigs of
heather. A few of these cocoons, selected from
those that show the best condition, are set aside and
left for the completion of the metamorphosis. The
resulting butterflies furnish the eggs or 'seeds'
whence, next year, will come the new litter of worms.
The rest of the cocoons are immediately subjected to
the action of very hot steam, which kills the chrysalis
in each just when the tender flesh is beginning slowly
to take form. Without this precaution the butterfly
would break through the cocoon, which, no longer
capable of being unwound because of its broken
strands, would lose all its value.

* * The cocoons are unwound in workrooms fitted up
for the purpose. First the cocoons are put into a
pan of boiling water to dissolve the gum which holds
together the several courses of thread. An operator
equipped with a small broom of heather twigs stirs
the cocoons in the water in order to find and seize the
end of the thread, which is then attached to a reel in
motion. Under the tension thus exerted by the ma-
chine, the thread of silk unwinds while the cocoon
jumps up and down in the warm water like a ball
of worsted when you pull at the loose end of the
yarn. In the heart of the unwound cocoon there re-
mains the chrysalis, inert, killed by the steam.

'* Since a single strand would not be strong enough
for the purpose of weaving, it is usual to unwind all

SILK 23

at once a number of cocoons, from three to fifteen
and even more, according to the thickness of the fab-
ric for which the silk is destined; and these united
strands are used later as one thread in the weaving
machines.

^^As it comes from the pan the raw silk of the co-
coon is found to have shed its coating of gum, which
has become dissolved in the hot water ; but it is still
coated with its natural varnish, which gives it its
firmness, its elasticity, its color, often of a golden
yellow. In this state it is called raw silk and has a
yellow or a white appearance according to the color
of the cocoons from which it came. In order to take
on the dye that is to enhance its brilliance and add
to its value, the silk must first be cleansed of its
varnish by a gentle washing in a solution of lye and
soap in warm water. This process causes it to lose
about a quarter of its weight and to become of a
beautiful white, whatever may have been its original
color. After this purifying process it is called
washed silk or finished silk. Finally, if perfect
whiteness is desired, the silk is exposed to the action
of sulphur, as I will explain to you when we come
to the subject of wool.

*^ Cocoons that have been punctured by the butter-
fly, together with all scraps and remnants that can-
not be disentangled and straightened out, are carded
and thus reduced to a sort of fluff kno\\Ti as floss-silk,
which is spun on the distaif or the spinning-wheel
very much as wool is treated; but even with the ut-
most pains the thread thus obtained never has the
beautiful regularity and the soft fineness of that

M THE SECRET OF EVERYDAY THINGS

which is furnished by unwinding the cocoon. It is
used for fabrics of inferior quality, for stockings,
shoe-laces, and corset-laces.

^ ^ The silkworm and the tree that feeds it, the mul-
berry, are indigenous to China, where silk-weaving
has been practised for some four or five thousand
years. To-day, when the highly prized caterpillar
is dying out in our part of the world, China and its
neighbor Japan are called upon to furnish healthy
silkworm eggs. Silk-culture was introduced into
Europe from Asia in the year 555 by two monks who
came to Constantinople with mulberry plants and
silkworm eggs concealed in a hollow cane ; for it was
strictly forbidden to disseminate abroad an industry
that yielded such immense riches. ' '

CHAPTER V

WOOL

WE live," continued Uncle Paul, "on the life
of our domestic animals. The ox gives us
his strength, his flesh, his hide ; the cow gives us her
milk besides. The horse, the ass, the mule work for
us; and when death overtakes them they leave us
their skin for leather with which to make our foot-
wear. The hen gives us her eggs, and the dog places
his intelligence at our disposal. But if there is one
anini'vll;!r.t, moio than another, comes to us from the
good God above, it is sureh^ the sheep, the gentle
creature that yields us its fleece for our garments,
its skin for our warm coats, its flesh and its milk for
our nourislmient. But its most precious gift is its
wool.

"From wool are made mattresses, and it is also
woven into cloth such as merino, flannel, serge, cash-
mere, and, in short, all the various fabrics best fitted
for protecting us from the cold. It is by far the most
desirable material for wearing apparel, cotton, not-
withstanding its importance, coming only second,
and silk, valuable though it is, being very inferior in
respect to serviceability. More than with anything
else we clothe ourselves with w^iat we strip from the
innocent sheep ; our finery comes for the most part
from its fleece."

26 THE SECRET OF EVERYDAY THINGS

^'But wool is very far from beautiful on the
creature ^s back/' commented Claire; ''it is all
matted and dirty, often fairly covered with filth. ' *

''It must take a good many processes,'' remarked
Marie, "to change that foul and tangled fleece into
the beautiful skeins of all colors with which we em-
broider such pretty flowers on canvas."

"Yes, indeed, very many," rejoined Uncle Paul.
"I have already told ^ you how sheep are washed and
sheared, and how the washing leaves the fleece white
or brown or black according to the color given to it
by nature. White wool can be dyed in all possible
tints and shades, from the lightest to the darkest,
whereas brown or black wool can take only somber
hues. White wool, therefore, is always preferable
to any other; but, beautiful as it is when freshly
washed and relieved of all impurity, it is still far
from having that snowy whiteness so desirable if it
is to remain undyed. It is bleached by a very
curious process which I will now describe to you.

"You have all doubtless observed that when
sulphur burns, with a blue-violet flame, it gives forth
a pungent odor that irritates the mucous mem-
brane of the nose and throat and causes a fit of
coughing. ' '

"That must be what we smell when we light a
match," Claire interposed. "If you breathe in the
least little whiff of it, it is perfectly horrid."

' ' Often enough it has set me to coughing unless I
was on my guard," remarked Emile.

"Yes, that is it,'^ their uncle replied. "Sulphur,

1 See "Our Humble Helpers."

WOOL 9n

in burning, becomes an invisible substance which
is dissipated in the atmosphere and betrays its
presence only by a detestable odor of the most
pungent quality. Invisible, impalpable, like the
air itself, this something that we know merely as a
disagreeable smell constitutes nevertheless a real
substance the existence of which cannot be doubted
by any one who has once been thro^\Ti into a fit of
coughing by inlialing it. It is called sulphurous
oxide, a new name to you and one to be kept in mind.
It will be worth your while to remember it, as you
will presently see. '^

*^ Sulphurous oxide, then,'' said Marie, *^is burnt
sulphur ; and it is something that can be neither seen
nor felt, but that nevertheless does really exist.
Whoever breathes it is immediately convinced of its
existence by the penetrating odor and by the fit of
coughing that follows.''

^^To what possible use," continued Uncle Paul,
^'can we turn this disagreeable gas, this invisible
substance that makes you cough worse than if you
had the whooping-cough! I will tell you. Despite
its repulsive qualities, it is what we have to depend
upon for giving to wool the whiteness of snow. An
example will demonstrate its efficacy to you. Go
down to the meadow and pick me a bunch of violets."

The violets were soon gathered from under the
hedge bordering the meadow. Then Uncle Paul put
a little sulphur on a brick, set it afire, and held the
bunch of violets, which he had slightly sprinkled with
water, over the fumes. In a few moments the
flowers, attacked by the sulphurous gas ascend-

28 THE SECRET OF EVERYDAY THINGS

ing from the blue flame, lost their color and turned
perfectly white. The change from violet to white
was plainly visible to the eye.

^^How curious that is!" exclaimed Jules. ^Must
see how the violets whiten as soon as they come over
the flame and feel the sulphurous oxide, as you call
it. Some were half white and half blue ; but the blue
has disappeared and now the bunch is all white,
without having lost any of its freshness to speak
of."

^ ^ Let us now, ' ' suggested Uncle Paul, * ^ try one of
the red roses there on the mantelpiece."

Accordingly the rose was held over the burning
sulphur, and its red color faded away just as the
blue of the violets had faded, giving place to white,
much to the wonder of the children, who watched
with breathless interest this marvelous transforma-
tion.

^^That will suffice for the present," Uncle Paul re-
sumed. '^What I have just shown you with violets
and roses might be demonstrated with innumerable
other flowers, especially red and blue ones : all would
turn white on being exposed to the sulphur fumes.
You will undertsand, then, that these fumes, which
we call sulphurous oxide, have the peculiar prop-
erty of being able to destroy certain colors and hence
to act as a bleaching agent.

^'If, therefore, you wish to bleach wool, to remove
the slight natural discoloration that stains its white-
ness, you proceed exactly as you have just seen me
do with the violets and roses. In a room with all
its doors and windows carefully closed the wool in

WOOL

its natural condition — that is, before it has been spun
into yarn — is hung up and a good handful or two of
sulphur is set on fire in an earthen bowl. The room
then becomes filled with sulphurous oxide and the
wool turns a beautiful white. ' '

** Would wool that is naturally brown or black turn
in that room full of sulphur smoke!'* asked Marie.

*^No," was the reply; '^its color is too fast to yield
to the action of sulphurous oxide. Only white wool
is subject to this action, under which it becomes im-
maculate. By the same process the straw of which
hats are made is bleached, also skins used for gloves,
and silk.

^^Wool varies in value accordiii.o: to the different
kinds of sheep
that have pro-
duced it, some
being coarse,
some fine and
silky, some made
of long hairs,
and some of
short. The most
highly esteemed,
that which is
used in weav-
ing fine fabrics,
comes from a
breed of sheep raised chiefly in Spain and known
as merino sheep. Finally, a goat native to the
mountainous countries of central Asia, the goat
of Cashmere, furnishes a downy fleece of extreme

Head of Merino Ram,
Before and after shearing.

30 THE SECRET OF EVERYDAY THINGS

fineness, an incomparable wool from which the most
costly stuffs are manufactured. This goat wears,
under a thick fur of long hair, an abundant down
which shields it from the rigors of winter and is
shed every spring. At that season the animal is
combed and the down is thus detached separate from
the rest of the hairy coat.''

CHAPTER VI

FLAX AND HEMP

HE inner coating of the stalk of flax and hemp,
as I have already told ^ you, is composed of
long filaments, very fine, flexible, and strong, which
are used like cotton in the manufacture of vari-
ous fabrics. Flax gives us such fine fabrics as
cambric, tulle, gauze, and laces of various kinds;
hemp furnishes us stronger stuffs, up to the coarse
canvas used for making sacks. Flax, as you have
already learned, is a slender plant with small flowers
of a delicate blue. It is so^vn and reaped annually,
and is raised especially in northern France, in Bel-
gium, and in Holland. The first of plants to be used
by man for making fabrics, it was turned to account
by the people of Eg}^pt, the land of Moses and the
Pharaohs, for the furnishing of linen bands with
which to wrap the mummies that have been reposing
in their sepulchres more than four thousand years.
So carefully, indeed, were they embalmed and then
wrapped in linen and enclosed in chests of aromatic
wood that to-day, after the lapse of centuries upon
centuries, the contemporaries of the ancient kings of
Egypt, of the Pharaohs in other words, are found
intact, though dried up and blackened by time.''
*^But in spite of all these precautions," objected

1 See "The Story-Book of Science."

THE SECRET OF EVERYDAY THINGS

Mummy-Case of KJia-Hor,

between two others.
(Boulak Museum, Cairo, Egypt.)

Claire, * ^ surely the mummies must liave gone to de-
cay if they were buried in the ground ! ' '

^^For that reason,'' replied her uncle, ^Hhey were
not buried; they were laid away in orderly rows in
spacious halls hollowed out of the solid rock of moun-
tains. These mortuary halls, to which dampness
never penetrated and the air had but little access,
have kept for us intact, swathed in their linen bands,
the bodies of the ancient Egyptians."

Uncle Paul next took up the subject of hemp, re-
lating the history of its cultivation in Europe from
early times and describing its appearance, with its
small green flowers and its slender stalk about two
meters in height. He explained that, like flax, it is

FLAX AND HEMP 33

grown both for its fibrous stem and for its seed,
known as hempseed, which is used as a favorite food
for certain singing-birds. From the
seed are obtained hempseed oil and
hempseed cake, the latter being
sometimes fed to cattle.

^^And what is flaxseed good forV
asked Emile.

*^From the seeds of flax," an-
swered his uncle, ''is obtained by
pressure an oil called linseed oil, Biossol^ng plant
which can be used for lighting, but llLr''''' '' '''^^
is chiefly employed in painting. For culinary pur-
poses it is almost worthless, being of no use at all
unless very fresh, and even then of but moderate
value. Its principal use, as I said, is in painting,
because of its quality of slowly drjdng and thus
forming a sort of varnish which holds fast the pig-
ment with which it is mixed. The coat of paint that
overlies, for example, the woodwork of doors and
windows is made of linseed oil in which has been
stirred a mineral powder, white, green, or any other
color chosen by the painter. When flaxseed is
ground it yields a powder much used for poultices,
being of an unctuous nature soothing to pains.

''When hemp and flax are ripe they are harvested
and the seeds are detached either by threshing or by
passing the seed-bearing ends of the stalks through
a strong iron-toothed comb. The comb is set up
across the middle of a bench on which two workmen
seat themselves astride, one at each end, facing the
comb. Then, by turns, they draw each his handful

THE SECRET OF EVERYDAY THINGS

of flax or liemp through the comb, thus separating
the seeds from the stalks.

*'Next comes the operation known as retting,
whereby the fibers of the bark are rendered separ-
able from the rest of the stem and from one another.

The gummy substance
holding them together has
to be disintegrated either
by prolonged exposure in
the field, where the flax
or hemp is turned over
from time to time, or,
more expeditiously, by
soaking the stalks in
Waaler, after first tying
them into bundles. The
resulting putrefaction lib-
erates the fibers. Dry-
ing, breaking, and hack-
ling them complete the separation of the fibers from
the useless substance of the stem and their reduc-
tion to a condition in which they are ready for use.
^^I Avill add that the fibrous part of hemp, as you
may know already, is far coarser than that of flax.
The filaments of the latter are so fine, that one
gramme of tow, spun on the wheel, makes a thread
nearly one hundred and fifty meters long. Never-
theless, this product of man's skill, this linen thread
that seems to reach the limit of fineness, is very
coarse indeed when compared with what is furnished
by the caterpillar and the spider. The highest de-
gree of delicacy attainable by our fingers with the

Hemp

Male (1) and female (2) plants
•f hemj). a, male flower ; b, fe-
male flower ; c, embryo.

FLAX AND HEMP 35

aid of the most ingenious machinery is but an enor-
mous cable in contrast with the thread manufactured
by a despised little worm. A single gramme of the
silkworm's thread, as we find it in the cocoon, repre-
sents a length of two thousand meters, whereas the
finest of linen thread of the same weight represents
only one hundred and fifty.

^ ' But even the slender filament spun from the silk-
worm's spinneret is incomparably coarser than the
spider's thread, the achievement of that master
artisan the very sight of whom evokes from you
senseless outcries of alarm. To w^eave the airy text-
ures intended to catch their prey, such as flies and
gnats and similar small game, as also to line the
dainty little sachets that hold their eggs, spiders on
their part produce a sort of silk. The silk matter is
contained in liquid form in the spider's body and is
forced out as required through four or five little
nipples called spinnerets, situated at the end of the
insect's stomach, each of these nipples being perfo-
rated with many tiny holes, the total number of which
for a single spider is reckoned at about a thousand.
Hence the spider's thread as it leaves the insect's
body is not a single strand, but a cord of a thousand
strands, although we commonly consider it of almost
infinitesimal minuteness. Our finest sewing silk is
a stout cable in comparison, and a human hair has
the thickness of ten twisted spider's threads or, in
other words, of ten thousand combined -elementary
filaments of spider-silk. How inconceivably fine
then must be a thread that needs to be multiplied ten
thousand times in order to equal a human hair in

36 THE SECRET OF EVERYDAY THINGS

size! The larger spiders that live in woods weave
webs of remarkable amplitude, requiring each at
least ten meters of thread, or ten thousand meters of
the elementary filament emitted by a single aperture
of the spinneret. But to make the entire web the
spider uses up only a tiny drop of liquid silk, of
which it would take hundreds of similar drops to
weigh a gramme. What machine of human inven-
tion or what fingers could spin for us a thread of
any such inconceivable fineness ! ' '

CHAPTER VII

WEAVING

'^TT^XAMINE a piece of cloth, woolen, cotton, or
r^J linen, and you will see that it is composed of
two sets of threads which cross one another, each
thread passing alternately over and under a trans-
verse one. Of these two sets one is called the warp,
the other the woof or weft, and their crossing pro-
duces the woven fabric, or cloth.

^*The work of weaving these threads into cloth is
done by means of a loom. I will try to describe to
you an old-fashioned hand-loom, which is much
simpler in construction than the modem power-
loom. A solid wooden framework supports a
cylinder in front and one at the back, and these
cylinders are turned each by a crank whenever
needed. The front cylinder, its crank within reach
of the operator seated ready for work, receives the
woven stuff a little bit at a time ; the other, fixed at
the opposite end of the machine, is wound with
threads in regular order side by side. These threads
will form the warp of the cloth, and they are
stretched with careful regularity between the two
cylinders the whole length of the machine. They are
divided into two sets, the odd-numbered threads
forming one set, the even-numbered threads the
other. Two heddles hold the two sets and keep them
separate without possibility of intermingling. A

38 THE SECRET OF EVERYDAY THINGS

heddle is a series of very line metal wires, or it may
be simply threads, stretched vertically between two
horizontal bars.'*

^ ^ The heddles are those two gridiron things in the
middle of the loom?'^ asked Claire.

*^ Precisely. At every wire or thread of the heddle
there is passed, in order, through an eye or ring, one
of the strands composing the two sets of the warp.

Modern Power-Loom

Now notice that by means of two pedals or levers
placed under the operator's feet the two heddles can
be made to rise and fall alternately. In this alter-
nate movement they draw by turns, up and down,
one the even threads and the other the odd threads
of the warp.

*^ While the warp is thus slightly open, all the even
threads on one side, all the odd on the other, the
operator sends the shuttle through the space separat-
ing the two sets. The shuttle is a piece of boxwood,
well polished so as to slide easily, tapering at each
end, enlarged in the middle, and provided with a

WEAVING 39

cavity that holds a bobbin of thread fixed on a very
mobile axle. This thread unwinds automatically
with the throwing of the shuttle, and is left lying be-
tween the two sets of threads of the warp. Then
with a pressure on one of __ P £_

the pedals the order of <1^^^~

these sets is reversed, the ^ Shuttle

thrparl^ that were above <*- ^ody of shuttle; &. yarn wound
UlieaUb LllclL W^IU ciuuve ^^ ^^j^^.^ ^. ^^ ^^^ through which

i^oooi'tio* Vkolr»TiT tVinao "ho the yarn is led and then passed out
paSSmg DeiOTV, mOSe Oe- through hole /; e, e, metal points.

low coming uppermost, and the shuttle sent in the
opposite direction leaves another thread stretched
across. This thread furnished by the shuttle and
passing by turns from right to left and from left to
right between the two lines of the warp forms what
is called the woof or weft of the cloth. ' '

' ' So the feet, ' ' said Marie, ' ' by pressing the pedals
make the odd and even threads of the warp move
up and dowTi, while the hands, sending the shuttle
from right to left and then from left to right, inter-
lace the thread of the woof with the warp.''

^ ' That is the double movement the operator has to
learn — the pressing of each foot in turn on the pedals
and the sending of the shuttle from one hand to the
other. But in order that the cloth may acquire suf-
ficient firmness, with no open spaces between the
threads, these two movements are supplemented by a
third. A comb-like instrument called a reed is used
to ^beat up' or press close together the threads of
the woof after every two or three passages of the
shuttle through the w^arp, or sometimes after every
passage, according to the nature of the fabric.

^^Such, in short, my dear children, is the process

40 THE SECRET OF EVERYDAY THINGS

by which all our woven fabrics of two sets of inter-
crossed threads are made, cloth, linen, taffeta, calico,
and a great many others/'

CHAPTER VIII

WOOLEN CLOTH

' T HAVE just given you a general description of the
A art of weaving. Now I propose to add some de-
tails relating to the more important products of the
loom. And first let us take up woolen cloth.

^^ Woolen cloth is woven of woolen yarn. As it
comes from the spinning-wheel or spinning-jenny
this yam has certain surface irregularities, little
bristling fibers standing up and crinkling with the
natural curliness characteristic of wool. In this
state the yarn would check the easy gliding of the
shuttle, which must shoot back and forth with great
rapidity ; and thus the work would be rendered labor-
ious and the woven fabric wanting in evenness of
texture. The surface must be made as smooth and
uniform as possible, the fluff flattened and held down
the whole length of the thread. This is done by
means of a preparation or facing with which the
threads of both the woof and the warp are coated.
In this preparation are glue, which holds down the
fluff, and oil, which makes the surface slippery.

^'Thus it is that, as it comes from the loom, cloth
is badly soiled, carrying as it does a coating of glue
and ill-smelling oil. Before these impurities become
seats of decay the cloth must be cleaned, and it must
be done as soon as possible. The operation is car-

42 THE SECRET OF EVERYDAY THINGS

ried out in a fulling-mill, which consists of a series
of heavy wooden clubs or beaters set in motion by
means of a wheel turning in a stream. The beaters
alternately rise and then fall with all their weight
to the bottom of a trough continually sprinkled by a
jet of clear water. The cloth is placed in the trough
where, the clubs beat it one after another for whole
days. But this energetic beating is not enough ; the
glue would disappear, but not the oil, which is more
tenacious and on which water has no effect. Accord-
ingly, recourse is had to a sort of rich earth, fine and
white, which has the property of absorbing oil. It
is called fullers ' earth. ' '

* ^ That rich earth could be used then for taking out
grease spots?" queried Marie.

*^It is used for that purpose. All you have to do
is to cover the grease spot for a while with a layer of
fullers' earth made into paste, iand the grease will
disappear, being absorbed by the clay. In many
countries it is used instead of soap for washing
clothes. ' '

*^What a funny kind of earth!" Claire exclaimed.
'^I should like to wash with it. What is it like?"

^^It is a white clay, greasy to the touch, taking a
polish when smoothed with the finger-nail, and mix-
ing readily with water, to which it gives a soapy look.
In France the best-kno^vn fullers' earth is found in
the departments of Indre, Isere, and Aveyron.

*^ Beaten with this earth for a number of hours by
the heavy clubs of the fulling-mill, the cloth loses the
oil with which it is impregnated. Soap-suds and
finally pure water finish the cleanings

WOOLEN CLOTH 43

^ ^ But the part performed by the fulling-mill is not
limited to cleaning the cloth; it also shrinks the
goods to half the original A\ddth and nearly half the
length. In this connection I will call your attention
to a precaution familiar to everj^ good housewife.
Before cutting out a garment she is careful to wet the
cloth so as to shrink it as much as possible. If this
precaution were not taken, the garment would shrink
so in the first washing that you could n't get into it."

**That is what happened to Emile's linen trous-
ers/' said Jules. "They came out of the wash so
short they hardly reached to his knees."

"A rope shrinks, too, when it is wet," remarked
Marie. "Once, after a rain, the clothes-line in our
back yard shrank so that it pulled out the hooks it
was fastened to."

"That reminds me of a little anecdote," said Uncle
PauL "When shortened by being wet, a rope exerts
so strong a pull that not only can it extract hooks,
but it can even lift immense weights. It is said that
Pope Sixtus the Fifth, when he was about to erect
in one of the public squares of Rome an obelisk
brought from Egypt at great expense, ordered under
pain of death the most profound silence during the
operation, so anxious were the operating engineers
on account of the enormous weight to be moved. I
will tell you, before going further, that obelisks are
tall, slender, four-sided columns engraved with a
multitude of figures and cro^\^led by a small pyramid.
They are in one piece, of a very hard and fine-grained
stone called granite. Their height, not counting the
pedestal that supports them, may reach fifty meters,

M THE SECRET OF EVERYDAY THINGS

and their weight may range between ten thousand
and fifteen thousand hundredweight. Judge, then,
whether the erection of this ponderous mass upon
its pedestal did not present difficulties.

*^To operate in perfect unison the numerous ropes,
pulleys, and levers used for raising the immense
piece, absolute silence was necessary so that not a
word should distract the workmen's attention. The
square was crowded with curious idlers watching
this mighty exertion of mechanical power. Com-
plete silence reigned, every one bearing in mind the
pope's order. But when the raising of the obelisk
had proceeded half-way, the enormous stone refused
to go further and remained leaning with all its
weight on the ropes. Everything was at a stand-
still. The engineers, at the end of their resources,
saw their gigantic task threatened with failure, when
suddenly from the midst of the crowd a man's voice
rose at the peril of his life. *Wet the ropes!' he
cried. ^Wet the ropes!' They wet the ropes and
the obelisk soon stood upright on its pedestal. The
tension of the cordage when soaked with water had
of itself done what an army of workmen had failed
to accomplish."

*^And what happened to the man who broke the
silence?" asked Emile.

^*The pope willingly pardoned him, you may be
sure. But let us return to our subject of woolen
cloth. You can now easily understand what happens
when this cloth is wet. It is made of crossed
threads, each one of which, on being soaked with
water, acts like a rope, that is to say it becomes

WOOLEN CLOTH

shortened. The result of this is a closer texture.
On drying, the cloth does not return to its original
state, as a rope when dry resumes its former length ;
it remains close, because the threads, held in position
by their interlacing, are not free to slip. Thus by
being put through the fulling-mill, where it is beaten
and wet at the same time, the cloth which was at first
loose enough to show the daylight between its
meshes, becomes a firm piece of goods with warp and
woof close together.

*'The two sides of a piece of cloth are not the
same : one, called the wrong side, shows the crossed
threads of the fabric, othermse known as the thread ;
the other, called the right side, is covered with a fine,
even nap, all lying the same way. This nap is ob-
tained by means of a kind of rude brush made of the
thorny burs furnished by a plant called teazel, or
fullers' teazel.

** Teazel lives from one to two years. Its stalk,
which attains the height of a
man, is armed with strong
hooked thorns and bears, at a
certain distance apart, pairs of
large leaves, each pair forming
a cup more or less deep in
which rain gathers. Growing
from the main stem are six or
seven branches, each termi-
nated by a strong elongated
head or bur composed of hard scales sharply pointed
and recurved at the end in the shape of a fine hook.
The plant is cultivated expressly for its burs, which

Fullers' Teazel

a, scale of the receptacle ;
b, corolla.

46 THE SECRET OF EVERYDAY THINGS

are used in great quantities in clotli-manufacture.
It would be difficult to replace this natural brush
with any similar tool made by our hands, for nothing
could give the same degree of needed stiiTness and
suppleness combined. Five or six of these burs are
placed side by side so as to form a brush, which is
drawn over the cloth always in the same direction.
The thousand hooks of the teazel, each as fine as the
slenderest needle, but elastic and supple, seize the
tiny fibers of surface wool lying between the threads,
and pull them out, laying them one on the other, all
pointing the same way. The result of this operation
is the nap which on the right side of a piece of cloth
covers and hides the thread.

* ^ But this nap is still imperfect : its tiny fibers are
of unequal length, some long, some short, at hap-
hazard, just as the hooks of the teazel brush drew
them from the threads. To make it all smooth and
even, it must be shorn; that is to say, large broad-
bladed shears are used to pare down the surface of
the cloth so as to leave the nap all of the desired
length. This completes the essential part of the
work. Sedan, Louviers, and Ellbeuf are the chief
cloth-manufacturing towns of France.'^

CHAPTER IX

MOTHS

*^ TN" our houses/' continued Uncle Paul, '*we have a
X redoubtable enemy to woolen cloth and every-
thing else that is made of wool — an enemy that in a
very short time will reduce a costly garment to rags
and tatters unless we are on our guard against the
ravager. Therefore it is worth our while to make
the acquaintance of this devourer of woolen goods,
this despair of the housewife, in order that we may
hunt it dovm with some success. You know the little
white butterflies that come in the evening, attracted
by the light, and singe their wings in the lamp-flame.
They are the ravagers of woolen fabrics, the de-
stroyers of broadcloth and other woolen stuffs.''

^ * But those little butterflies, ' ' objected Claire, ^ ^ are
feeble little creatures to tear in pieces anj^thing so
substantial as broadcloth."

^'And for that very reason it is not the butterfly
itself that we are afraid of; the delicate little flut-
terer is perfectly harmless. But before turning into
a butterfly it is first a caterpillar, much like the silk-
worm; and this caterpillar is endowed with a vora-
cious appetite that makes it gnaw substances ap-
parently uneatable, such as wool, furs, skins,
feathers, hair. To the caterpillar and its butterfly
we give the name of moth. ' '

48 THE SECRET OF EVERYDAY THINGS

** There are caterpillars, then, that eat cloth and
even hair?'^ asked Marie.

^' There are only too many of them," was the reply.
**One of these caterpillars, one that some day will
turn into a pretty little butterfly all powdered with
silver dust, would feast right royally on your woolen
frock ; and another would find much to its taste your
fur tippet, which keeps your shoulders warm in
winter. ' '

** There can't be much taste in a mouthful of fur,
I should think, and it must be pretty hard to digest.'^

**I don't deny it, but those caterpillars have
stomachs made expressly for that sort of diet, and
they accommodate themselves to it very well. A
worm that eats fur and digests hair knows nothing
in the world so good, and one that gnaws old leather
would turn away with aversion from a juicy pear, a
piece of cheese, or a slice of ham, all of them re-
pugnant to its taste. Every species has its prefer-
ences and, according to its mode of life, possesses a
stomach designed to find nutriment in substances ap-
parently far from nutritious. On the moth's bill of
fare are skins, leather, wool, woolen cloth, fur, and
hair. The larva does not merely feed on these ma-
terials, but it also makes from them a movable house,
a sheath that covers its body, leaving the head free,
and this house it carries about with it.

**A11 butterflies of the moth class have narrow
wings bordered with an elegant fringe of silky hair
and folded lengthwise on the back in repose. Of the
three principal species the distinguishing character-
istics are as follows :

MOTHS

*'The woolen moth has black upper wings tipped
with white, while the head and lower wings are white.
Its grub, or larva, is found in woolen goods, and it
is there that it makes for itself a sheath from the bits
of the gnawed fabric.

*'The fur moth has silver-gray upper wings with
two little black dots on each. Its grub lives in fur
goods, which it denudes, a hair at a time.

^^ Finally, the hair moth lives, in its grub state, in
the curled hair used for stuflfing cushions and
couches. In color it is of a uniform pale red.

**The moth most to be feared is the one that feeds
on woolen cloth. Let us discuss its habits more in
detail, for in spite of its ravages you will admire,
with me, the skill it displays in making itself a coat.
To protect itself so that it may live in peace, the grub
fashions for itself a sheath
from the bits of wool cut and
chopped with its sharp little
teeth. In thus cutting down
these upstanding hairs, one by
one, the worm shears the cloth
and makes a threadbare spot.
The shearman himself could not
have operated with such nice
precision. But there is noth-
ing so disfiguring in new cloth
as these shorn spots showing
here and there the warp and
woof of the fabric, while all the rest retains its vel-
vet finish. Furthermore, the mischief is not always
confined to the shorn spots: too often it happens

Clothes-Moth

With piece of cloth at-
tacked by larva. (Cross
and line show natural
sizes.)

50 THE SECRET OF EVERYDAY THINGS

that the tiny destroyer attacks the threads them-
selves and makes holes here and there in the cloth,
so that the latter is found to be nothing but a worth-
less bundle of rags. The bits of wool thus cut away
serve the worm either as food or as building-mate-
rial for its movable house, its sheath.

^^This latter is most deftly put together, consist-
ing on the outside of tiny bits of wool fastened to-
gether with a little liquid silk emitted by the worm,
and on the inside of silk alone, so that a tine lining
protects the creature ^s delicate skin from all rough
contact."

^^Just think of it,'^ exclaimed Jules; '^the detest-
able devourer of our woolen clothes lines its own
coat with silk ! "

**And that is not all,'' continued Uncle Paul.
*'The little creature indulges in the luxury of as-
sorted colors. Its coat takes the hue of the cloth in
process of destruction, and thus there are white
coats, black coats, blue coats, and red coats, accord-
ing to the color of the material. If this latter hap-
pens to be of variegated tints, the worm takes a bit
of wool here and a bit there, making for itself a sort
of harlequin outfit in which all the colors represented
are mingled at haphazard.

*^ Meanwhile the worm continues to grow and its
sheath becomes too short and too tight. To lengthen
it is an easy matter: all that is required is to add
new bits of wool at the end. But how is it to be
made larger?"

^'If I had to do it," Claire replied, ^'I should run

MOTHS 51

my scissors down lengthwise, and in the opening I
should insert another piece. ' ^

^ ' The ingenious insect seems to have taken counsel
of Claire, or of an even better tailor,'' said Uncle
Paul. ^^With its teeth for scissors it cuts open its
coat all down its length and inserts a new piece. So
skilfully is this insertion made, so neatly are the
seams sewed with the silk, that the most expert of
dressmakers would find it hard to pick any flaw in
the workmanship."

''These moth-woiTns must be very skilful, I ad-
mit,'' said Marie, "but I should n't like to have them
practice their art on my clothes. How are they to
to be prevented?"

' ' To protect garments from moths it is customary
to place in our wardrobes certain strongly scented
substances such as pepper, camphor, tobacco. But
the surest safeguard is to inspect the garments fre-
quently, shaking them and beating them and expos-
ing them to the sun. All moths love repose and
darkness. Garments that are shaken occasionally
and hung in the light are not at all to their taste ; but
those that are laid away for months or years in a
dark place offer gust the kind of snug retreat they
are looking for, the ideal abode for the raising of a
family. Go to your chests of drawers and your
wardrobes very often and shake, air, and brush the
contents ; then you will have no moths. Vigilance is
here worth more than pepper and camphor. Fi-
nally, kill all the little white butterflies you see flut-
tering about your rooms."

52 THE SECRET OF EVERYDAY THINGS

'*But those little butterflies do no harm whatever,
you told us, ' ' objected Emile. * * It is only the worms
that gnaw our clothes. ' '

* * True enough ; but those butterflies will lay eggs
by the hundred, and from every egg will come a de-
vouring worm. The destruction of the flying moth
means therefore deliverance from some hundreds of
future moths/'

CHAPTER X

NAPERY

<<yTEMP is woven into coarse material for towels
iJL and sacks, and even into finer material for
sheets, chemises, table-cloths, and napkins. From
flax is obtained still finer goods for the same pur-
poses. Sometimes the same material contains both
hemp and flax. Thus the goods known as cretonnes,
manufactured at Lisieux and its' environs, have the
warp of hemp and the woof of flax. Sometimes,
again, it is cotton that is mixed with hemp. Ticking,
for example, is a very close fabric used for making
coverings for bolsters and also men's summer
clothes. Generally it is all hemp, but certain grades
have a cotton woof. So it is that the three kinds of
vegetable fiber — hemp, flax and cotton — can be used
two together in the same material, which gives goods
of greater variety and better adapted to the infinite
uses for which they are destined.

* ^ Goods of this sort generally bear the name of the
country that produces them: such are the goods
called Brittany, Laval, Valenciennes, Saint-Quentin,
Voiron. Others are named after their inventor, as
Cretonne, which derives its name from a manu-
facturer, Creton, who centuries ago gained a great
reputation for linen-manufacture. One kind of
linen, very fine and close, used for handkerchiefs and

54 THE SECRET OF EVERYDAY THINGS

various articles of attire, such as veils, collars, and
cuffs, is called batiste in honor of Baptiste Chambrai
who was the first to make this material, and who in-
troduced its use about five centuries ago.

''Material composed only of hemp and flax, either
separate or together, is commonly called linen.
Certain qualities distinguish these goods from cot-
ton. To a delicate skin they have a cool and soothing
feeling, whereas cotton, owing to its nap, which is
slightly rough, produces a kind of tickling that may
be positively disagreeable. Thus a cotton handker-
chief irritates nostrils that have been made sensitive
by a prolonged cold ; but a linen handkerchief has not
the same objectionable quality. And again, for
dressing wounds it is customary to use linen or hemp
bandages and lint obtained from old rags of the
same material, since cotton, no matter how fine, and
soft, would only increase the irritation of the wound
by its rough contact with the quivering flesh.
Finally, hemp and linen as used for underwear keep
the skin in a state of coolness that is very agreeable
in the heat of summer, but which may under certain
conditions prove very disagreeable. Let perspira-
tion be checked, let the body, poorly protected by its
cool covering of hemp or linen, cool off quickly, and
we are in serious danger. Cotton, on the contrary,
stimulates the skin slightly, keeps it warm, and
affords better protection when perspiration is ar-
rested. In this respect it is preferable to linen and
hemp. But I will come back to this subject after
some details that I wish to give you in a subsequent
talk on the conservation of heat.

NAPERY 55

^^ As soon as hemp has been spun into thread by the
long and patient labor of the distaff, it is sent to the
weaver, who coats it with a preparation of glue to
facilitate the play of the shuttle, stretches it on his
loom in parallel lines, and weaves it as I have al-
ready explained to you, each foot pressing in turn
one of the pedals that operate the warp, and the two
hands throwing, one to the other, the shuttle which
stretches the thread of the woof between the two sets
of warp threads. A good washing cleans the cloth,
removing the preparation I have referred to and all
impurities contracted during the weaving. But that
is not enough to produce the beautiful white cloth
that the housewife cuts into shirts and sheets.
Hemp and flax are, in fact, naturally of a light red-
dish tint, so firmly fixed that only after repeated
washings will it entirely disappear; which explains
why sheeting is whiter as well as softer the longer
it is used.

**As a first step in bleaching, the linen is spread
on the ground in a well-mown field, where for wliole
weeks it remains exposed to the daylight and to the
damp night air. The prolonged action of air and
sun, dryness and dampness, at length fades the red-
dish color, which subsequent washings will, little by
little, finally remove altogether.

^^This bleaching by exposure to sun and rain is
very slow. Moreover, when the operation has to be
carried on uninterruptedly and on a large scale it
is very costly, because it renders unproductive con-
siderable stretches of land. Consequently in hemp,
linen, and especially cotton factories recourse is had

56 THE SECRET OF EVERYDAY THINGS

to means that are at once more energetic and
more expeditious. You remember how easily and
economically wool and silk are bleached by burning
a few handfuls of sulphur, thus generating a gas
called sulphurous oxide. It is only necessary to ex-
pose wet wool and silk for a few hours to the action
of this gas to give them the dazzling whiteness of
snow.''

^^Is that the way hemp, flax, and cotton are
treated? '^ asked Marie.

**Not quite, although the method employed much
resembles that used for wool. Sulphurous oxide
would have no effect here, so difficult is it to destroy
the natural color of hemp, flax, and cotton. Some-
thing stronger, something more drastic, must be
used.''

^^But that sulphur smoke is pretty strong; it
pricks your nose like needles, and makes you cough
till the tears come.''

*^Yet it is nothing in comparison with the drug
used for bleaching. This drug is also a gas — that
is to say, a substance as impalpable as air, but at the
same time a visible gas, for it has a light greenish
color. It is called chlorine. If you breathe a whiff
of it, you are immediately seized with a violent cough
such as you would never get in winter, however cold
it might be. The throat contracts painfully, the
chest is oppressed, and you would die in frightful
torture if you inhaled this formidable gas three or
four times in succession. You can see, then, what
precautions one must take in factories not to expose
oneself to the terrible effects of chlorine."

NAPERY 57

*^Aiid what does it come from, this gas that
strangles people if they breathe ever so little of itV
asked Claire.

'^It comes from common salt, the same salt with
which we season our food. But I must add that in
salt it is not found all by itself ; it is mixed with an-
other substance which renders it harmless, even
wholesome. Once freed from this partnership it is
murderous, a frightfully destructive agent. I am
sorry I cannot show you its astonishing power in
destro>4ng colors ; but nothing prevents my telling
you about it. Imagine a sheet of paper not only
covered with characters traced by the pen but
daubed all over with ink. Now plunge this into
chlorine gas, and writing and ink-blots all disappear
instantly, leaving the sheet of paper as white as if it
had never been used. Suppose, again, you put
chlorine into a bottle of ink. The black liquid fades
quickly and soon there is nothing left but clear water.

** After this you can understand that the material
to be bleached has to be subjected to the action of
chlorine for only a few moments in order to turn
whiter than through long exposure in the field.''

''If the deep black of ink is destroyed so quickly,''
remarked Marie, ''the pale reddish tinge of hemp or
linen is not likely to hold out very long. ' '

"Wool and silk," Claire observed, "ought to be
bleached that way too : it would be much quicker."

"The manufacturers are very careful not to fol-
low any such method," was the reply. "This gas
corrodes wool and silk, soon reducing them to a mere
pulp. ' '

58 THE SECRET OF EVERYDAY THINGS

*^And yet cotton, flax, and hemp can stand it,^'
Claire rejoined.

*'Yes, but their resistance to the action of drugs
has not its equal in the world, and this resistance
gives them a very peculiar value. Think in how
many ways cloth of this sort is used, and what severe
treatment it undergoes : repeated washing with cor-
rosive ashes, rubbing with harsh soap, heating, ex-
posure to sun, air, and rain. What then are these
substances that withstand the asperities of washing,
soap, sun, and air, that even remain intact when all
around them goes to decay, that brave the drugs
used in manufacturing and emerge from these mani-
fold tests softer and whiter than before? These al-
most indestructiblr^ piibstnucos are hemp, flax, and
cotton; and they have no rivals/'

Uc.vj....

CHAPTER Xi

CALICO

IT now remains for me to tell you about the prin-
cipal weaves of cotton. First there is percale,
which has a firm and close texture and a smooth sur-
face, and is much used for shirts, curtains, covers,
and sometimes for table and bed linen. Ornamented
with colored designs, it is also used for dresses.

*^ Percale, diminutive of percale, as its name
shows, is a fabric of inferior quality and of trans-
parent texture, being very loosely woven. Its
thread is flat and its surface fluffy and plush-like,
whereas in percale the thread is round and the sur-
face smooth. It lacks firmness and does not last
long. It is used chiefly for lining.

*^ Common calico is less fine, less firm, and cheaper
than percale, but is used in general for the same pur-
poses.

*' Muslin is a very fine, soft, light material, the
most delicate of all cotton goods. There are some
muslins that for fineness almost rival the spider's
web, and of which a piece several yards long could be
contained in an egg-shell. Among muslins are
classed nainsook, organdie, and Scotch batiste.

^^ Cotton has a decided superiority over flax and
hemp in that it readily takes any desired color or
ornamental design, the dyes being quickly absorbed,

60 THE SECRET OF EVERYDAY THINGS

lastingly retained, and shown off to the best ad-
vantage. Who does not know these admirable goods
in which the most varied and brilliant colors are ar-
tistically combined and our garden flowers are re-
produced in astonishing perfection? Some of these
prints are decorated with flowers such as no garden
could furnish. Cotton alone lends itself to this rich-
ness of coloring, hemp and flax being absolutely in-
adequate. Cotton goods ornamented with colored
designs are called prints, and they first came from
India, where their manufacture has been known for
a very long time. To-day the factories of Rouen,
Mulhouse, and England supply these goods to the
whole world. It will interest you to hear about some
of the methods employed by the calico-printer in his
delicate work. How were those beautiful designs
obtained, so clear and bright, that ornament the
most inexpensive dress? That is what I propose to
tell you in a few words.

*^ First the fabric is bleached with the greatest
care so that no dinginess of its own shall dim the
brightness of the colors to be received. Energetic
washing, over and over again, and the powerful
bleaching agent I have just spoken of, namely
chlorine, make the cotton perfectly white.

*^Now comes an operation that would fill you with
astonishment if you happened to see it: it is the
operation of singeing. I must tell you to begin with
that all cotton thread, however perfect the spinning-
machine producing it, is covered with a short down
or fluff consisting of the tip-ends of the vegetable
fibers standing up by their own elasticity. At the

CALICO 61

time of wea\H[ng this fluff is laid flat by means of a
preparation of glue, so as to leave perfect freedom
for the play of the shuttle ; but now this preparation,
which would greatly interfere with the setting of the
colors, has disappeared to the last trace, and the fluff
of the threads stands up free again. Well, on such
goods, all bristling with tiny filaments, the colored
designs would not take well ; there would be uneven-
ness of tint, ill-defined outlines; cracks and seams,
in fact. The surface must be as clean and smooth as
a sheet of paper. It would be well-nigh impossible
to obtain with shears such as are used for shearing
woolen cloth a surface as smooth as the subsequent
operations demand. Accordingly it is the custom to
have recourse to the use of fire. The material is
passed with the necessary rapidity before a broad
jet of flame, which thoroughly burns off every bit of
fluff without in the least damaging the fabric itself.
Nothing is more extraordinary to the novice than to
see a piece of calico or percale or even muslin pass-
ing through the menacing curtain of flame without
catching fire.''

**And who would not be surprised!'' exclaimed
Marie. ''I should think the delicate fabric would
certainly catch fire."

**You would think so, but there is no danger if the
material passes quickly along and does not give the
heat time enough to penetrate beyond the fluff. Let
ns dwell a moment on this peculiarity, which will en-
lighten us concerning a very remarkable attribute
of cotton.

**You know what happens when you put the end

62 THE SECRET OF EVERYDAY THINGS

of a piece of cotton thread into the lamp flame. The
part thrust into the flame is consumed at once, but
the fire spreads no farther and goes out just at the
point where the thread ceases to be enveloped by the
flame. With a piece of linen or hemp thread the re-
sult would be a little different : the thread would con-
tinue to burn more or less beyond this limit. That
is on account of the different manner in which cotton
on the one hand and flax and hemp on the other act
under the influence of heat. Cotton is rather im-
pervious to heat; flax and hemp, on the contrary,
offer only feeble resistance to its spreading. I will
not say any more on this point now, but will return
to it some day with the necessary details.

*' The, few facts I have given you are sufficient to
explain what takes place in the singular operation of
singeing. If the fabric passes through the fire
quickly and at an even rate of speed, the flame en-
velops it on both sides and even traverses the meshes,
burning off all the fluff without injuring the threads
themselves, because the heat has not time to spread
further.

**To banish once for all your incredulity in regard
to this singeing process I will show you an experi-
ment which, indeed, has no close connection with the
calico-printer's art, but which illustrates the dif-
ferent degrees of inflammability possessed by dif-
ferent substances. What should you say if I were
to tell you that live coals can be placed on the finest
muslin Avithout burning it in the least?"

**I should say, 'Seeing is believing,' " answered
Claire.

CALICO 63

^^Then you shall see, Miss Incredulous. Take a
piece of muslin, as fine as you please, and wrap it
tightly around one of the brass balls that ornament
the top of the stove. Tie it securely underneath
with a string so that the muslin will touch the metal
in every part. Now take from the open fire a live
coal and apply it with the tongs to the muslin that
covers this kind of doll's head.''

Claire followed these directions with scrupulous
care : the live coal was touched to the muslin, and,
greatly to the surprise of all the children, the deli-
cate fabric remained perfectly intact.

^^Go still farther," commanded Uncle Paul.
^^Take the bellows and make the live coal burn as
brightly as you like, letting it rest on the muslin
while you do so."

Claire worked the bellows, the coal became red-
hot all over, and still the muslin underwent no
change, appearing to be quite incombustible.

^^Why, this is unbelievable!" she cried. ''How is
it that the muslin can stand the touch of a live coal
without burning the least bit ? "

''Wliat protects it from the fire," replied her
uncle, ''is the metal underneath. The brass, a sub-
stance easily penetrated by heat, takes to itself the
heat of the coal and leaves none for the muslin, which
is much harder to heat. But if the delicate fabric
were by itself, it would burn at the first touch of the
live coal."

Several times during the day Claire repeated this
experiment by herself, each time more astonished
than before at this strange incombustibility.

CHAPTER XII

DYEING AND FEINTING

^ RRIVED at this point, the cotton cloth is ready

to receive the colors. This operation involves
the use of means so varied and technical knowledge
so above your understanding that I should not be
understood if I undertook to enter into some of the
more elaborate details/'

**I supposed, on the contr..ry,'' said Claire, **that
it was a very simple thing and that the colors were
put on the cloth with a paint-brush just as I should
do, though not very well, on a sheet of paper.'*

** Undeceive yourself, my dear child: the paint-
brush has nothing to do with printed cottons, nor yet
with the other kinds of goods embellished with
colors. Done with a paint-brush, the designs would
not be lasting, but would disappear with the first
washing. The slightest rain would make the colors
run and would turn them into horrible shapeless
blots. To resist water, and sometimes vigorous
washing with soap, the colors must penetrate the
fabric thoroughly and become embodied in it.

*'Let us see how this result is arrived at, taking
black for an example. This color is obtained in
various ways, notably with ink, the same that we
use for writing. Well, if we immersed a strip of
white material in this liquid it would come out black,

DYEING AND PRINTING 65

but the color would have no staying power. A little
rinsing in water would remove most of the ink, and
the small amount remaining would give only a pale
tint, very insufficient and soon washed out. In order
to give a deep and lasting black the ink, when it is
applied to the fabric, must be in an unfinished state,
and it must finish itself in the cloth ; the ingredients
of which it is composed must mingle and become ink
in the very substance of the threads. Under these
conditions the black, made on the spot and permeat-
ing the minutest fibers of the cotton, acquires all the
desired fixity and intensity. Let us, then, before
going further, examine the ingredients of which ink
is composed.

*' There are found growing on oak-trees certain
globular formations of
about the size of a billiard
ball and with the appear-
ance of fruit. But they
are not really fruit; they
have nothing in common
with acorns, the real fruit

of the oak. They are ex- Gall-fly (female), natural size;

- , , 6, male antenna magnified

crescences caused by the

sting of a tiny insect known as the gall-fly. This
insect stings the leaf or tender twig with a fine gimlet
that arms the tip-end of its stomach, and in the
microscopic incision it deposits an egg. Around this
egg the sap of the tree gathers, finally forming a
little ball which by degrees becomes as hard as wood.
The insect hatched from the egg develops and grows
in the very heart of this ball, whose substance serves

eS THE SECRET OF EVERYDAY THINGS

it as food. When it has grown strong enough it
pierces the wall -of its abode with a small round hole
through which it escapes. That is why you see most
of these balls pierced with a hole when they fall to
the ground toward the end of autumn. These round
excrescences are called gall-nuts or oak-apples, and
they furnish one of the ingredients of ink, one of the
materials used for dyeing black.

^^The other ingredient is green copperas. At the
druggist's you may have seen a substance looking
something like broken glass of a light green color
with spots of rust. That is green copperas. It is
obtained by dissolving iron in an excessively cor-
rosive liquid known as oil of vitriol or sulphuric
acid. This terrible liquid, so dangerous in inex-
perienced hands, dissolves iron as easily as water
dissolves salt or sugar ; and in this solution, after a
certain time, crystals are formed. It is this crystal-
lization that gives us our green copperas, a substance
having none of the dangerous qualities of the oil of
vitriol used in making it, but one that can be handled
without the least risk, though its taste is most dis-
agreeably tart. This substance dissolves very read-
ily in water.

'^That is all that is needed for making ink. Let
us boil a handful of pounded gallnuts in water; we
shall obtain a pale yellowish liquid. Also, let us dis-
solve some copperas in water, and the latter will turn
a very pale green with a yellowish tinge. What will
happen on mixing the two liquids, one yellow and
the other green 1 Nothing very remarkable, it would
seem. And yet no sooner do these two liquids

DYEING AND PRINTING 67

mingle than there is produced a deep black, the very
color of ink/^

^'And so the ink comes all of a sudden/' said
Marie.

^^Yes, the very instant the gallnuts and the cop-
peras meet in the water that holds them in solution.
If ink for writing is desired, however, a little differ-
ent method must be followed so as not to have an
excess of water, which would weaken the color. To
the liquid resulting from boiling the gallnuts there
would simply be added the undissolved copperas with
a little gum to give brilliance to the ink. I have gone
out of my way in describing to you this mingling of
two liquids in order to show you the more clearly how
the union of two substances, each having little or no
color, can produce a color totally unlike either of the
original shades. From two liquids, one a pale yel-
low, the other a pale green, you have ,iust seen ink
spring into being with startling suddenness. Re-
member this phenomenon, for it will explain certain
results of dyeing that are very astonishing to the un-
initiated. Bear in mind that sometimes perfectly
colorless substances can produce magnificent colors
by being united.

^^Now that we know how ink is made, let us return
to the subject of dyeing black. We put a piece of
percale to soak in water in which gallnuts have been
boiled ; then, when it is well saturated, we take it out
and dry it. Y\liat, now, will be its color!''

^'It will be the color of the gallnut water,"
answered Claire; ^'that is to say, a pale and dirty
yellow. ' '

68 THE SECRET OF EVERYDAY THINGS

** Right; but if the fabric thus saturated is dipped
into a solution of copperas, what will happen f

^ ^ That is not hard to guess, ' ' was the reply. ' ' The
copperas, finding gallnut dye on the surface and in
the texture of the cloth, all through it in fact, will
immediately form ink, which will color the percale
black. '^

*^And more than that,'' added Marie, ^Hhe dye will
penetrate the goods evenly in every part, since the
saturation with gallnut water extends to the very
tiniest thread of the material.''

^^Yes; and so you see that in this way the black
dye is formed on the spot, in the very heart of the
cotton threads. Thus we obtain a fast color, all the
necessary conditions being complied with.

^'A great many other colors — red, violet, brown,
yellow, lilac, no matter what — are produced in simi-
lar fashion. First the material to be dyed is sat-
urated with a solution that will develop the desired
color, or make it spring into existence, on encounter-
ing another solution, and will set the color by mak-
ing it one with the fabric itself. This preparatory
substance which in a second operation is to mix with
the dyestuff so as to develop and fix the color is
called the mordant and varies in kind according to
the tint desired, so that by changing the mordant
different colors may be obtained with one and the
same coloring matter."

**In the way you have just explained to us," said
Marie, *^we get cloth dyed all one color. I should
like to know how patterns of several colors on a
white ground are made."

DYEING AND PRINTING 69

* ^ That is done by printing or stamping. Imagine
a small wooden block or board on which is engraved
in relief the design to be reproduced. Clever en-
gravers skilled in all the details of ornamental design
prepare these blocks, which are sometimes veritable
masterpieces of art; and it is these that constitute
the calico-printer ^s all-important equipment.

^'To take a simple example, let us suppose the
workman proposes to put a black design on a white
ground. On a large table in front of him he has the
piece of percale which unrolls as he needs it; in his
right hand he holds the printing-block. The en-
graved design, which stands out in relief, he
moistens slightly with a fine solution of gallnuts, and
then applies the block to the goods. The parts thus
touched are the only ones impregnated with this
preparation, the rest of the percale remaining as it
was before. He continues thus, each time dipping
the engraved face of the block into the gallnut
preparation, until the piece of cloth has received the
impression throughout its entire length.

^^That done, all that is necessary is to dip the
goods into a solution of copperas to make the design
appear in black, since the ink forms wherever the
wooden mold has left a deposit of gallnut water, all
other parts remaining white.''

**It is simpler than I had thought," said Claire,
**and much simpler than using a paint-brush, as I
supposed at first must be the way."

''The operation can be made still simpler. As a
rule the coloring matter and the mordant, that is to
say the substance that brings out the color and fixes

70 THE SECRET OF EVERYDAY THINGS

it, act onlv under the influence of li?at. Accord-
ingly, the process is as follows. The two ingredi-
ents, mordant and coloring matter, are mixed to-
gether and reduced to a fine pap with which the en-
graved surface of the block is moistened and then
immediately applied to the fabric. The preparation
thus deposited gives only one color, one alone, de-
termined by the nature of the mordant and the color-
ing matter. If the design is to be multicolored, as
many blocks musf be used as there are tints, each
block representing only the part of the design having
the color it is to imprint on the goods. Thus the
piece of percale passes through the workman's hands
once for red, again for black, a third time for violet,
in fact as many times as there are colors in the de-
sign, however little they may differ from one an-
other. ' '

**It must be a very delicate piece of work," re-
marked Marie, '^to put the different parts of the de-
sign exactly in the right place so as to get from them
all a pattern ^^'ith the various colors joining perfectly
and never overlapping."

''The calico-printer's skill makes light of this
difficulty. The design comes out as clear as a painter
could make it with his brushes. To complete the
description in a few words, when all the colors have
been applied, the fabric is removed to a closed room
where it receives a steam bath. Heat and moisture
aiding, each dye mixes with its mordant, which in-
corporates it with the fabric, and beautiful bright
tints spring forth as by enchantment where the en-
graved blocks had left only a sorry-looking daub, ' '

CHAPTER XIII

( (

DYESTUFFS

OULDX'T you tell us, Uncle Paul/^ said
Marie, *'how all those colors we see on printed
goods are obtained? There are such beautiful reds,
blues, violets, that real flowers can hardly compare
with them.''

^^Yes, I will tell you. Let us first take madder, the
most valuable of

dyestuffs on account f^'''' * -"^ '^^ ( ^^f ^"^^

of the beauty and **
fastness of its col-
ors. It is the root
of a plant cultivated
in France, chiefly in
the department of
Vaucluso, and of
about the size of a
large feather, red-
dish yellow in color.
The preparation it
undergoes before
being used in dye-
ing consists simply
in reducing it to very fine powder and purifying it as
much as possible.

*' Madder by itself imparts absolutely no color to

bladder

1. branches with flowers and fruits: 2, the
rhizome: a, blossom; b, the pistil; c, two dif-
ferent fruits.

72 THE SECRET OF EVERYDAY THINGS

any stuff, be it silk, wool, cotton, or whatever other
you please. One might boil for days at a time a
piece of percale in water containing powdered mad-
der; the fabric would remain white. For the
color to take form and impress itself on the stuff
there is some essential condition lacking.''

*^No doubt it needs what you call the mordant,
that substance that mixes with the dye to bring out
the color and fix it on the goods, just as gallnuts
bring out the black of ink by mixing with copperas.''

' ' That is it : it lacks the mordant. In the case of
madder this is sometimes iron-rust and sometimes
a white substance resembling starch and called
alumina, which is obtained from very pure clays. If
the material to be dyed is first saturated with a
strong solution of alumina, it takes a dark red tint
on being dipped into boiling water containing a
proper amount of powdered madder. If the quan-
tity of alumina is small, the resulting tint is simply
rose-color. Thus by var^^ing the proportion of the
mordant any shade can be given to the fabric, from
the deepest red to the palest pink.

**With iron-rust for mordant other colors quite
unlike the preceding are developed. A liberal quan-
tity of rust gives black, a small quantity violet — al-
wavs with madder, be it understood. Finallv, if the
mordant is a mixture of alumina and rust the color
produced is a chestnut bro^vn, intermediate between
red and black, and varying in shade according to the
proportions of the ingredients used. You see, then
— and it cannot fail to surprise you — that with a
single dyestuff, madder, it is easy to obtain a numer-

DYESTUFFS 73

ous series of tints ranging from dark red to pale
pink, from deep black to delicate violet, and includ-
ing also the chestnuts or mixtures of red and black.

**Let us suppose the calico-printer has stamped
the different mordants on the goods with his print-
ing-block and has artistically grouped them to obtain
bouquets of flowers. This done, the cloth appears
merely soiled with unsightly blotches, the iron-rust
showing with its dirty yellow, while the alumina,
being colorless, remains invisible. But as soon as
the piece is ^Dlunged into a boiling bath of madder
each mordant attracts to itself the coloring matter
dissolved in the water, incorporates it, and with it
forms such and such a color according to its nature.
The reds, pinks, blacks, violets, chestnuts, all come
out at the same time before our astonished eyes,
which at first misrht ima2:ine themselves beholding
the birth of enchanted bouquets.''

''If you had not explained this curious operation,"
said Claire, ''I should have been astonished to see
those magnificent printed bouquets taking shape all
by themselves in the confusion of that boiling vat."

''Then it is in that one vat," added Jules, "con-
taining only 'water and madder, that there are
formed all at the same time the reds, pinks, and
violets for the flowers, the chestnuts for the bark of
the branches, and the blacks for the shadows. The
bouquets lack only the green of the leaves to be com-
plete."

"Madder does not give green; another substance
and another operation are necessary to obtain that
color. Nevertheless, who could fail to perceive the

THE SECRET OF EVERYDAY THINGS

importance of madder, that one substance which fur-
nishes so many hues, all remarkable not merely for
their beauty but also for their unequaled perma-
nence ? No other dyestutf contains in itself so many
excellent qualities. '^

**And the other colors — blue, for example — how
are they obtained?'' asked Marie.

''The most lasting blue is the product of a plant

called the indigo-plant. It
is too cold in our part of the
world to raise this plant, but
it grows on the warm, damp
plains of India. It is the
leaves that are used. They
are green at first, but if they
are allowed to go to decay
in water containing a little
lime, a substance having a
superb blue color and called
indigo is formed from them.
"A very beautiful yellow
remarkable for its fastness
is prepared from a plant
that grows around here and
is known as woadwaxen or dyers' greenweed, bear-
ing flowers closely resembling those of the mignon-
ette, so famous for its sweet odor. By mixing
this yellow with blue we obtain the green that Jules
spoke of as needed for the leaves of the bouquets.

''A small, rather ugly-shaped insect gives the dyer
his most beautiful reds. It is known as the cochi-
neal, and it lives all its life in one spot, as do the lice

Woadwaxen or Dyers'
Greenweed

DYESTUFFS 75

of our rose bushes. It infests a fleshy plant whose
branches are flattened in the shape of a palette and
studded with tufts of thorns. This plant is known
under the names of nopal, cactus, Indian fig, and
Barbary fig. Mexico produces most of the cochineal.
The insect is gathered from the
nopal, killed by immersion in boiling
water, and dried in the sun. It then
looks like a little wrinkled seed.
About one hundred and forty thou-
sand insects are required to make Female cochineal
one kilogram in weight. It is only eomS?ce'^'""?Lin1

, 1 •! ii 1 • 1 • shows natural size.)

necessary to boil the cochineal m
water to obtain a red liquid which deposits as sedi-
ment the beautiful coloring matter known by the
name of carmine. Wool and silk are dyed scarlet
with cochineal.

^*I will conclude with a few words on the brightest,
clearest of all dyestuffs, but unfortunately, also, the
most changeable, the most evanescent. Recall the
splendid hues now given to wool, silk, and above all
to ribbons. The rainbow alone can rival them.
Now do you know the origin of these colors, so pure,
so bright, so charming to the eye ? They come from
a horrid, malodorous substance called coal-tar.

*'In the first place you should know that illuminat-
ing gas is obtained by heating coal red-hot, in large
iron vessels to which no air is admitted. The heat
liberates at the same time gas for lighting and tar
which is set aside by itself; there is then left a kind
of coal, light, shiny, full of holes, and called coke.
Let us turn our attention to the tar only, which

76 THE SECRET OF EVERYDAY THINGS

despite its disgusting appearance is one of the most
marvelous products known to the manufacturing
world. By treating it first in one way, then in an-
other, and after that in still another, there are ob-
tained from it a number of very different substances,
some resplendent like mother-of-pearl or the scales
of fishes, others white and powdery like fine flour,
and still others resembling limpid oil and having in
certain instances a strong and disagreeable odor and
in others an aromatic fragrance. When this separa-
tion is complete, we have at our disposal various sub-
stances which further processes will transform into
colors of all kinds. One of these substances derived
from coal-tar, and at first a colorless oil, becomes an
azure blue that would not disfigure the wing of the
most gorgeous butterfly; another, at first a floury
powder, reproduces exactly the colors yielded by
madder ; a third gives shades of red beside which the
queen of flowers, the rose, would look pale. But one
capital fault ^ is common to most of these splendid
colors obtained by man's skill from the somber coal:
hardly any of them can stand the least washing with-
out injury, and even light alone fades them quickly.
** Colors that are really fast, those that last as long
as the fabric that bears them, and can without fad-
ing stand light and soap, are particularly the colors
obtained from madder, the browns and blacks into
the making of which gallnuts have entered, the blues
from indigo, and the yellows of woadwaxen. Beware
of a dye that charms the eye but turns dim under the
first ray of sunlight or with the first washing. ' '

1 This fault has now been corrected. — Translator,

CHAPTER XIV

HEAT-CONDUCTION

0 give you a thorough understanding of the part
played by woven fabrics in our clothing and
coverings I must now call your attention to certain
attributes of heat. The little I can tell you on this
subject will be illustrated in many cases by im-
portant practical applications. So be very attentive.

''A firebrand can with impunity be taken up in
the fingers by one end if the fire is confined to the
other; there is no risk of our being burnt, even
though the fingers be very close to the ignited part."

^'I have often noticed that,'^ said Jules, 'Svlien
poking a comer of the fire in winter, and when to
save time I have used my fingers instead of the
tongs. '^

''But one could not, without getting burnt, grasp
the apparently cold end of a piece of iron, even a
pretty long one, if red at the other end. Neither
could one take hold of the handle of a flat-iron warm-
ing on the heater. The hand must be protected by a
thick holder.

''These two familiar examples, charcoal and iron,
show us that heat is not conducted with the same
readiness by all substances. It easily makes its way
through iron, which becomes very warm a long dis-
tance from the part directly heated; but it is With

78 THE SECRET OF EVERYDAY THINGS

difficulty that it permeates charcoal, which remains
cold a short distance from the ignited section.

**In this respect all substances are divided into
two classes : those that are easily permeated by heat
or that conduct it well, and those that are difficult
for heat to permeate or that conduct it poorly. The
first are called good conductors, such as iron; the
second, poor conductors, such as charcoal.

*^ Among the good conductors are all the metals —
iron, copper, silver, gold, and so on. Non-metallic
substances, such as wood, charcoal, brick, glass, and
the various kinds of stone, are, on the contrary, poor
conductors. Conductivity is still poorer in powdery
substances, such as ashes, earth, sawdust, and snow;
also in fibrous substances, such as cotton, wool, silk,
and hence the fabrics woven from these materials. ' '

**Then,'^ said Marie, *'the holder with which we
grasp the handle of a flat-iron keeps the hand from
being burnt because it prevents the heat from going
farther. It is a poor heat-conductor. ' ^

**Yes, it checks the heat of the iron and prevents
its reaching the hand. In like manner the various
iron implements that have to be thrust into the fire
at one end and heated are furnished at the other end
with a wooden handle by which they can be grasped
without risk of burning the hand.

*^0f all substances air is the poorest heat-conduc-
tor, as proved by the following curious experiment.
A scientist named Rumford, to whom we are in-
debted for some noteworthy researches on the sub-
ject of heat, had some frozen cheese placed in the
middle of a dish. Over this cheese was poured a

HEAT-CONDUCTION 79

light froth made of beaten eggs, and then the whole
was put into a very hot oven to cook the eggs quickly.
Thus was obtained a sort of omelette soiifflee, piping
hot, and in the middle of it was the frozen cheese,
which had lost none of its coldness. How could the
cheese remain frozen in the oven? The explanation
is to be found in the poor conductivity of air. It was
air, imprisoned in the froth of the eggs, that shel-
tered the cheese from the heat of the oven, obstructed
the heat in its passage, and prevented its going far-
ther. The heat not reaching it, the cheese in the
center remained frozen."

^^I should like," said Emile, ^Ho have had a taste
of that cheese, so cold under its hot crust of cooked
eggs!"

^^Now," resumed Uncle Paul, ^'I come to the prac-
tical application of the peculiarities I have just
pointed out to you. A substance that conducts heat
poorly may serve two purposes which at first seem
contradictory and yet at bottom are alike in every
respect. It can be used to protect both from the cold
and from the heat, to keep an object warm as well as
to keep it cool. To cool off is to lose heat; to get
warm is to gain it. Accordingly, the point is to
check, in the first case, the inner heat that might
escape, and, in the second, the outer heat that might
enter. Both requirements are met by the same
means, the interposition of an obstacle impervious to
heat in either direction; that is to say, a covering
that is a very poor heat-conductor."

Then what keeps out the cold keeps out the heat
too?" queried Marie.

80 THE SECRET OF EVERYDAY THINGS

^^ Precisely, singular though it may seem to you.
The same covering that prevents loss of heat in any
given body also prevents its receiving what might
come from outside. A few examples will prove this
to you. Let us first recall that chief among poor
conductors are powdery and fibrous substances.
This property they owe mainly to the air retained
between one particle and another, one fiber and an-
other, just as water is retained in the innumerable
little cavities of a sponge. These substances are
used as a protection from cold and heat alike.
Ashes will furnish me my first example.

^*If on going to bed at night we cover a bed of live
coals with ashes, we shall find the coals still alive
the next morning. The ashes, by keeping out the
air, check combustion ; but they do still more : at the
same time that they check combustion they serve to
retain in the coals nearly all their original heat, so
that the next morning they are as glowing-hot as the
night before. This result is due to the obstacle that
ashes as a powdery substance oppose to the escape
of heat. Under this powdery covering the embers
remain alive because they cannot send out their heat,
a poorly conducting body standing in the way.

^ ' These same ashes that prevent the cooling of an
object can also prevent its acquiring heat. I will tell
you later how the little girls in my village used to go
and borrow fire from a neighbor, returning with a
live coal on a bed of ashes in the hollow of their
hand. This shallow layer of ashes prevented their
burning themselves, its poor conductivity arresting
the heat of the glowing ember.

HEAT-CONDUCTION 81

'^The two examples are convincing: you see the
same substance, ashes, acting as protector, first from
the cold and then from the heat, keeping the live
coals from cooling off and the hand from getting
burnt/'

CHAPTEE XV

HUMAN HABITATIONS

^* "^ PASS to other examples. To keep the contents

of a soup-tureen warm, what do we do 1 We en-
close the tureen in a woolen coverlet ; we wrap it in
several thicknesses of a soft material which acts as
a very poor heat-conductor because of its fibrous
texture.

^^But suppose, on the other hand, we wish to keep
something at a low temperature ; we again avail our-
selves of this same quality possessed by fibrous sub-
stances. In summer, to exclude the heat from our
ice-creams and sherbets we use a jar set into another
of much greater size, filling the intervening space
with wool, cotton, or rags. Thus the same wool,
cotton, or other filling that maintains the warmth of
the soup in the tureen will also serve to maintain the
coldness of the frozen preparation in the jar.

^'Ice, which is one of the most urgently needed
supplies in warm countries, is sometimes trans-
ported long distances under a burning sun. The
'United States, for example, ships every year great
quantities of ice to China and the Indies, and the
vessels engaged in this traffic cross seas where the
highest temperature prevails. Nevertheless the
cargo reaches its destination almost intact, thanks to
the non-conducting material protecting it from the

HUMAN HABITATIONS 83

heat, this material being sawdust, straw, dry leaves,
or shavings, with which care is taken to cover com-
pletely the cakes of ice heaped up in the hold.

^'An ice-house for keeping through even the hot-
test summer weather the ice gathered in winter con-
sists of a deep excavation lined with brick in prefer-
ence to stone, because the former is a much poorer
heat conductor. A thick layer of straw is also
placed next to the bricks. The ice is stored when
the weather is very cold, the cakes being packed
closely and then flushed with w^ater, which freezes
and renders the whole one compact mass. Over all
is laid a bed of straw, and on top of this are put
planks loaded with stones. Finally the ice-house is
roofed with thatch. The very same procedure
would be adopted if it were desired to keep from
escaping the warmth present in the excavation.'^

^'Then,'' said Marie, "this thatched roof and
layer of straw would be just the thing for making a
snug retreat that would keep out the cold. ' '

"Yes, this snug retreat, made of straw and similar
material to withstand the severities of winter, is ex-
actly what WQ find in the extreme north of Europe,
where the cold season is so rigorous. Houses of
masonry like ours would there be inadequate, be-
cause brick and stone would offer but an imperfect
obstacle to the dissipation of the interior warmth.
For those arctic habitations some building material
is required of less conducting power than brick and
stone, some material that will retain the interior
warmth just as ashes retain the heat of the live ooals
that they cover. To this end masonrj^ gives place to

84 THE SECRET OF EVERYDAY THINGS

walls of thick planks or even of lo2:s laid lengthwise
one upon another. So far so good, since wood con-
ducts heat much less readily than stone ; but it is not
enough. A double enclosure or wall is built of these
planks or logs, and the space between the two single
walls is filled with moss, leaves, or straw. Thanks
to this multiple enclosure made of materials that act
as very poor heat-conductors, the warmth given out
by a stove always alight is kept from escaping even
when the severest cold prevails outside.

^^The most curious application of powdery sub-
stances as a protection against cold is found in the
use of snow for constructing winter dwellings.''

^*What,'' cried Claire, ^^do they build houses of
snowT'

^'Not exactly houses like ours, but huts in which
the occupants are very well sheltered. ' '

' ^ And where is that ? ' '

*^In Greenland, to the northeast of America, in the
frigid zone, as we have already seen. ^ There, where
the rigors of the climate are well-nigh inconceivable
to us, the Eskimos live in huts built of regular blocks
of hardened snow laid in circular courses and round-
ing toward the top, with a sheet of ice capping the
dome to admit the light. A bench of snow next to
the wall encircles the interior and is provided with
rude bedding of heather and reindeer skins for the
repose of the inmates at night. No fireplace is ever
found in these abodes, since there is no wood for
fuel ; and, moreover, a fire would melt the snow hut.
A wick of moss fed with seal oil burns in a little stone

1 See "Our Humble Helpers.'*

HUMAN HABITATIONS 85

pot and serves both to melt snow when water is
needed for drinking and to maintain an endurable
temperature in the hut, thanks to the very slight con-
ductivity of the snow walls. Outside, meanwhile,
the cold is of an intensity such that even our severest
winters offer no comparison. If one leaves the hut,
immediately face and hands turn blue and become
quite numb; the skin cracks open under the action
of the frost; the breath forms needles of hoar-frost
around the nostrils, and the tears freeze on the edges
of the eyelids.''

^*What a frightful country!'' Claire exclaimed.
**And do people really live there?"

^' Yes, there are people who give the sweet name of
home to that forbidding land. They live there the
year round, in summer under skin tents, and when
winter comes in snow huts."

*^But why don't they build themselves houses of
stone?" asked Jules.

'' Because they would freeze in them," was the
reply, ^^for lack of fuel to keep a hot fire going all
the time. Snow is the only available material that
can conserve the heat of the little lamp and maintain
an endurable temperature in the hut ; and this it does
by reason of the poor conducting power of its
powdery mass.

^ ^ The various powdery or fibrous substances, such
as snow, ashes, sawdust, shavings, straw, moss, wool,
cotton, feathers, all well adapted to the keeping out
of either cold or heat, owe this peculiar property in
great part to the air held prisoner in their in-
terstices. The air imprisoned in the foam of beaten

86 THE SECRET OF EVERYDAY THINGS

eggs prevents the heat of the oven from penetrating
to the frozen cheese that I told you about in relating
a curious experiment. The same foam, inflated with
air, would protect from the cold any heated body
that it might envelop. Air by itself can be used to
prevent the dissipation of heat if it is so placed that
it cannot be renewed and mix with the free air of the
atmosphere. I will now call your attention to an in-
stance in which this property of air is turned to ac-
count in our houses where the climate is severe.

^^The warmth in a room escapes to the outside
through the walls, floor, and ceiling, these never
being perfect non-conductors. For this waste of
heat there is hardly any remedy in our dwellings of
brick and stone. But there is one avenue of escap-
ing heat that can be easily closed. I refer to the
windows. The panes of glass offer but a very im-
perfect obstacle to the outflow of heat. In order to
supply a more efficacious barrier without lessening
the transparency of the windows and their admission
of light, it is customary to build, as it were, a wall
of air behind the panes; that is to say, we fill the
opening in the wall with two windows, one on the out-
side and the other on the inside, thus obtaining in
the space between the two similarly glazed frames
a layer of immobile air, a sort of transparent wall
which the heat from within cannot pass through.
That is what we call a double window. ' '

CHAPTER XVI

CLOTHING

<*T If TE say of one piece of goods that it is warm,
V V of another that it is cool. What do we mean
by that? Have fur and woolen cloth a heat of their
own that they communicate to us? Do we demand
of wool, down, or cotton some supplementary heat
furnished by their own substance?

*'Not at all; for none of these materials, be it the
silkiest dowTi or the softest fur, has any heat of its
own, and they cannot supply it to us. Their office is
limited to preventing the loss of such heat as is
within us, the natural heat that our bodies generate
simply by living. Garments and wraps are poor
conductors interposed between the human body,
warmed by the vital heat, and exterior objects
which, colder than the body, would otherwise lower
its temperature. They are to us what a shovelful of
ashes is to the . firebrands on the hearth. They do
not warm us, but they preserve our natural heat;
they do not add anything to us, but they prevent
loss.'*

* ^ Then a garment that we call warm, ' ' said Marie,
*4s not really any warmer than another, but only
keeps the heat of the body in better?''

^ ' That is it, exactly. You see, apart from all idea
of finery and pleasing adornment, the value of a gar-

88 THE SECRET OF EVERYDAY THINGS

ment from the sole point of view of real usefulness
in retaining heat depends above all on its poor con-
ducting power. The worse conductor it is, the bet-
ter the garment will fill its office. In this respect
wool heads the list of materials used in our textile
goods ; offering the most resistance to the radiation

Silkworm (about natural size)

of the body's heat, it is the most serviceable in pro-
tecting us from cold. Silk, cotton, hemp, and flax
are far inferior to it. And that is as it should be.
Wool is the sheep's clothing; therefore its attributes
are assigned to it by Providence for protecting from
cold the chilly animal that wears it. Silk, cotton,
hemp, and flax have in the order of nature other
uses: silk insures the safety of the caterpillar and
its chrysalis in the cell of a firmly woven cocoon ; the
feathery down of the cotton-plant causes the seeds
to float in the air and enables them to travel long
distances and germinate in far-off places; the mis-

CLOTHING

sion of hemp and flax is to strengthen long and
fragile stems with their fibers. What was not cloth-
ing by nature became so by man's art, but it never
acquires to the same degree the valuable qualities
that belong to wool, the natural clothing of the ani-
mal it covers.

^ ^ Cotton in its turn conducts heat less readily than
hemp or flax ; hence cotton goods are preferable to
linen for underwear that comes next to the skin and
by its direct contact with us is so effective in main-

Cotton-Plant
Branch and (a) opened boll.

taining our temperature. With cotton, sudden chills
and arrested perspiration, with all their dangerous
consequences, are less to be feared than with linen.
*^But of all substances air is the poorest heat-con-
ductor. Therefore we envelop ourselves, as it were,
with air. Our textiles of wool, cotton, etc., are in a
way only a sort of network for retaining the air in
their innumerable meshes. This layer of air main-
tained all round our body protects us from cold the
more effectively the thicker it is and the less liable

90 THE SECRET OF EVERYDAY THINGS

to renewal. Hence it is not the heaviest and closest-
woven fabric that is the warmest, but supple, soft
stuff that receives an abundance of air throughout
and holds it captive in its meshes, as do cotton-wool
and do\\Ti.

^^Furthermore, between the body and its clothing,
and retained by the latter, is found an envelop of air
which we must take into consideration since it con-
stitutes a natural lining that nothing could replace.
To play its part well this lining of air must be of a
certain thickness, which is assured by our wearing
clothing that is loose enough but not too loose, be-
cause in the latter case the air, being renewed too
easily, would be constantly replaced by cold air and,
reversing its function, would cause a loss of heat in-
stead of a gain. '^

^'I must confess. Uncle Paul," Marie interrupted
again, '^I had no idea air played any such part in our
clothing. AYho would have imagined that we keep
ourselves warm by holding a little stale air around
us! Doubtless it is the same with our bed-cover-
ings?"

^^ Precisely the same. Our bed-covers and hair
mattresses are only barriers preventing the loss of
natural heat. The light feathers, wool, cotton, hair
composing them retain the air in abundance in their
fluffy mass and thus form a non-conducting envelop
which the heat of the body cannot pass through.

** Mattresses are even made of air alone without
any fibrous material whatever. A substantial cas-
ing of canvas fastened in a frame is kept in shape by
means of springs arranged inside. This pouch is

CLOTHING 91

filled with a layer of air, which is both soft and yield-
ing, so as to insure comfort, and very effective in re-
taining heat. It is far preferable to heavy straw
mattresses, being cleaner, less cumbersome, and
easier to handle.''

CHAPTER XVn

ASHES — POTASH

WASHING linen with ashes or lye is one of the
most important operations of housekeeping.^
In a large wooden tub the soiled linen is arranged
with some care, on it is strewn a layer of wood-ashes,
and over the whole is poured a quantity of hot water.
This water, carrying with it the active constituents
of the ashes, filters through the linen and removes
the stains, running out continually in a small stream
through an opening left in the bottom of the tub and
collecting in a bucket from which it is drawn and re-
placed on the fire, to be poured over the ashes again
when it is hot. The whole day is spent at this work.
From morning to night always the same boiling
water passes through the contents of the tub from
top to bottom, cooling off on the way, running out,
and returning to the fire to begin the same journey
over again.

^^ Washing with the help of wood-ashes is much
more effective than washing with hot water alone.
The part played by the ashes is what we will now
consider, and in this connection let us have recourse
to a simple experiment.

**We drop a few handfuls of ashes into a pot of
water and set it to boil. After boiling a little while

1 This method of washing, still retained in certain rural districts
of Europe and not unknown in America, has now largely given place
to quicker and easier processes. — Translator.

ASHES— POTASH 9S

we leave the contents to cool off. The ashes settle
at the bottom and the water above becomes clear.
Well, we shall detect in this liquid a peculiar odor
in all respects like that which comes from the wash-
tub; and we shall also find that it has an acrid, al-
most burning taste. This smell of lye and this acrid
flavor were not in the water to begin with; they
come from the ashes which have imparted a certain
property not in the water originally.

'^ Ashes must therefore be composed of at least
two elements differing from each other. The more
abundant of these two cannot dissolve in water, but
gathers in a mass at the bottom, forming an earthy
layer; the other, on the contrary, constituting only a
very small part of the whole, dissolves easily in
water and gives to it its ovm peculiar properties,
especially its odor and acridness. If, in order to
make ourselves better acquainted with it, we wish to
obtain by itself the part yielded by the ashes, nothing
could be easier. All that is necessary is to put the
clear liquid containing the solution in a vessel on the
fire and heat it until all the water has evaporated.
There will remain a very small amount of whitish
matter looking a little like kitchen salt. But it is not
kitchen salt, far from it ; it is quickly recognized by
its taste, which is unbearable. Put a little of this
whitish powder on your tongue and you will instantly
feel a prickly and painful sensation as if from a
burn. The part touched would indeed be burned to
the quick, just as if it had been seared with a red-hot
iron, if the powder first underwent a certain prep-
aration which I will not enter into now. The skin

94 THE SECRET OF EVERYDAY THINGS

of the hand, although much less sensitive, is pained
by prolonged contact with this harsh substance,
which gnaws the skin and makes it crack and bleed.
Wool, silk, feathers, hair, horn, leather, and al-
most everything of animal origin yield to its cor-
rosive action and are at last reduced to a pulpy paste.
Such is the active element in ashes, the element in
fact that gives lye its drastic properties. It is called
potash.''

'^Then washing with ashes produces its effect by
means of the potash which the water dissolves and
carries off through the layer of ashes 1 ' ' This from
Marie.

'^That is it, exactly.''

*^ Potash, which bites the tip of the tongue when
one tastes it, and the skin of the fingers on handling
it, also, you say, quickly destroys wool, silk, leather
and many other things of animal origin. Then,
woolen and silk goods should not be washed with
ashes: the potash in the ashes would injure them."

^*They would, in the end, go all to pieces in the
wash. ' '

*'Hemp, cotton, and flax," continued Marie, ^^must
be very tough not to be injured in a liquid capable of
reducing wool to a pulp. ' '

*^I have already told you that textiles of these
materials are endowed with an exceptional and ad-
mirable resistance which increases their value a
hundredfold. Here you have a conclusive proof.
A thick woolen stutf would come from the lye-wash
all a sticky paste ; a frail cotton fabric would emerge
intact. ' '

ASHES— POTASH 95

^* Washerwomen's hands are all cracked," ob-
served Claire. ^'I have seen some of these poor
women with the skin worn off their fingers. It must
be the potash from the lye that makes these
wounds ? ' '

*'It is the potash. It eats into the hands as it
would into a woolen stocking."

**Why, then," asked Emile, '^do they put ashes
in the w^ash-tub when this frightful drug, potash, de-
stroys woolen things and tortures the washerwomen
by eating into their hands? Why do they not simply
use hot water?"

*^That is exactly the point we are coming to. To
get rid of an oil or grease spot what would you do,
my dear child? Would you simply use water, hot
or cold?"

*^ Certainly not. I know very well that water
alone, even if boiling hot, would not take out the
grease. I should use soap."

*' Right. Well now, you must understand that if
soap is good to take out grease spots it is just be-
cause it contains potash, as I will explain to you
presently in detail. One more question : to wash
dishes that are very dirty, very greasy, is hot water
sufficient?"

**No; I think in that case ashes are boiled in the
water, and with their help the grease comes off all
right. ' '

*^Your answer is correct. Hot water alone can-
not remove the grease, but hot water together with
ashes does the work very well. In this case again
the effect produced by the ashes is due to the potash

96 THE SECRET OF EVERYDAY THINGS

they contain. This substance, in short, this potash
that Emile calls a frightful drug, possesses a prop-
erty very useful in housekeeping : it is the property
of dissolving greasy substances of whatever sort
they may be, whether oil, lard, suet, or tallow, and
making it possible for them to be carried off by
water. Try to take out with water alone the oil spot
that soils a piece of linen : all your patience, all your
efforts, will fail ; the spot will remain afterward what
it was before, and the water will have accomplished
nothing. But if we first dissolve a pinch of potash
in the water and then use it for washing, the spot
will disappear without any trouble. To sum up,
potash dissolves greasy substances and consequently
gives water the power to take out spots produced by
those substances.

^^Now, more than half the stains on soiled linen
belong to this class: they are grease spots. Pro-
longed contact with the human body leaves our gar-
ments full of impurities ; little accidents at table soil
the table-cloths and napkins with oil and grease;
kitchen service accounts for all sorts of greasy de-
posits on the kitchen towels. To wash out these im-
purities on which water has no effect we are com-
pelled to invoke the aid of potash, which is found in
the ashes that lie ready to hand on the hearth.
Ashes, then, play an indispensable part in the work
of the laundry; with their energetic assistance hot
water is able to efface not only all grease spots, but
also countless other stains that mere washing would
not always remove.

**The ashes used are those that come either di-

ASHES— POTASH 97

rectly from wood or from wood that has been con-
verted into charcoal. The best are those from bak-
ers' ovens, on account of their larger proportion of
potash. The dense wood of the trunk and larger
branches of a tree contain less potash than the small
branches and the leaves. Hence the fuel used for
heating ovens, namely bundles of fagots, yields bet-
ter ashes than we commonly find on our hearths.
Finally let me add that coal-ashes are absolutely
valueless and would even be injurious."

CHAPTER XVIII

SOAP

^^'^"■^HE ashes of plants that grow on the seashore

and in the waters of the sea itself contain, in-
stead of potash, another substance possessing almost
the same properties and called soda. ' '

^^ There are plants, then, in the sea?" asked Jules.

^ ' Certainly, my boy ; and most curious ones. Our

fields are not more covered with plants than is the

bottom of the sea; but marine plants differ much

from terrestrial ones. Never
do they have flowers, never any-
thing to compare with leaves,
never any roots; they fasten
themselves to the rock by glu-
'* ing the base of the stem to it,
d but derive from it no sustenance
Seaweeds iAigcB) ^h^tever. It is Water and not

1, Dicfyota dichotoma .- a,

c?sToo^an;;T'ver'tio;T:ecaon the soil that iiourishes them.

of same. 2, Plocamium j^^ ,-, , -, ■•

cocci/neum: f, tetraspore ; There arc somc that resemble

g, stichidium; h, branchlet . i • t m i

with a cystocarp. VISCOUS thougs, plaitcd ribbous,

or long manes; others that take the form of little
tufted bushes, of downy topknots, or of waving
plumes; there are some of pinked strips, others
coiled in a spiral, and still others fashioned like
coarse, slimy strings. Some are olive-green, some
pale rose ; others are yellow like honey, and others,

SOAP 99

again, of a bright red. These strange plants are
called alg*ae, or seaweeds.

^*For a long time the only way to obtain soda was
to gather such marine plants as were cast upon the
shore by the waves and to cut do\vn the various kinds
growing at the w^ater's edge. As soon as this ma-
terial was quite dry it was burned out of doors in a
ditch, so as to get the ashes. But as this method
was slow and did not furnish enough soda to supply
what is needed in the arts, which use an enormous
quantity, men of science set their wits to work to de-
vise more fruitful and more expeditious methods.
To-day soda is prepared from common salt, the sea
furnishing inexhaustible quantities. Immense fac-
tories, each mth a large force of workmen, are occu-
pied exclusively with this work. ' ^

^'Soda, then, is something very important!" asked
Claire.

'^Yes, one of the most important articles used in
manufacture. Many things of the greatest utility
and in everyday demand need for their fabrication
the cooperation of soda. The fine, white paper on
which you write, the magnificent colored designs of
our calicoes and other prints, the glass in our bottles
and window-panes, our soap, that invaluable aid to
cleanliness, all these things and countless others re-
quire the use of soda, or of potash, which I will call
its sister, so much do they resemble each other."

*^Then potash, too, must be manufactured on a
large scale?" was Marie's query.

''The manufacture of potash stands on a par, in
importance, with that of soda ; but potash is always

100 THE SECRET OF EVERYDAY THINGS

dearer because less abundant. The greater part of
it is obtained from the ashes of terrestrial plants.
For this purpose in well-wooded countries such as
certain regions of Russia and North America, whole
forests are cut down and the wood is burned on the
spot, out in the open air, just for the sake of the
ashes.''

'^Do you mean to say," said Marie, incredulously,
*^that those enormous fires that consume whole
forests are lighted for nothing but to get the ashes?''

^^For nothing but to get ashes from which to ex-
tract the potash. I hasten to add that this prodigal-
ity is possible only in countries where forests are
abundant and the population very sparse. In such
regions wood is of little value, as there are no people
to use it for heating. But in our part of the world,
where the forests are far from sufficient for the needs
of heating, great care is taken not to waste wood
thus. In the forest-covered mountains of the
Vosges, for example, it is the practice, in order to ob-
tain ashes, to burn only the very small branches,
which are of little value, and the dead leaves.

^^The manufacture of potash is conducted in the
manner I showed you a little while ago in our elemen-
tary experiment. First the ashes are boiled in
water, and then the clear liquid is drawn off and
evaporated to the last drop over a fire. The incrus-
tation at the bottom of the kettle is the potash,
which is further purified by methods that do not
concern us here.

^ ' The properties of these two valuable substances,
soda and potash, are nearly identical. Both have a

SOAP 101

beautiful white color when very pure ; at first sight
you would take them, in their unpowdered form, for
white marble. Both dissolve very easily in water,
to which they give the odor and taste of lye. Both
have a very disagreeable taste ; a tiny piece, less than
a pin's head, placed on the tongue, as I have already
told you, would burn like a red-hot iron and take off
a piece of the skin. Both eat into leather, wool, and
silk ; and both dissolve greasy substances. You have
seen this last attribute demonstrated in the use of
ashes in washing; and the same characteristic is
found again in soap, as I will now explain to you.

^'Of all the stains that are left upon linen by daily
use, the most frequent, as you know, are grease-
spots, which water alone cannot remove. To take
out these spots they must first be rendered soluble
in water by adding a substance which will give them
solubility. Potash and soda fulfil this condition ad-
mirably. But direct use of these harsh substances
is impracticable. What would become of the wash-
erwoman's hands, rubbing the clothes mth drugs
that burn the skin like fire I In a few moments they
would be nothing but one horrible wound. And that
is not all: the linen itself, however strong it might
be, would finally be destroyed by such prolonged con-
tact with these excessively drastic substances. Pot-
ash and soda, therefore, can in no wise be employed
directly in washing. What is to be done then ? The
difficulty is solved by adding another substance
which takes away their formidable strength without
too greatly weakening their solvent effect. To tem-
per the excessive energy of potash and soda, to

102 THE SECRET OF EVERYDAY THINGS

soften in some measure the two terrible drugs and
make them easy to handle, they are mixed with a
greasy ingredient, sometimes oil, sometimes tallow;
and from this mixtures comes soap. ' '

** There is oil or tallow in soap?" asked Emile.

**Yes, my dear boy, and plenty of it. The rest
consists of a little potash or soda. These latter give
soap the power to clean ; the oil and tallow preserve
the hands and the linen from a contact which without
any intermediary substance would be very danger-
ous."

'^And yet, apart from the greasy feeling, there is
nothing in soap to show that it has any tallow, still
less oil. Oil runs, and soap does not."

^'Oil runs only when alone. Once united with
potash or soda, it ceases to be liquid and becomes a
block of the consistency of cheese. Singular though
it may seem to you, it is nevertheless true that soap
is composed of either soda or potash and a greasy
substance, oil or tallow.

^^Soap for common use is made from soda and oil
of inferior quality, or beef suet or mutton tallow.
Let me tell you how soap in large quantities is made.
Into great vats of boiling water the desired quantity
of soda is dropped, then the due proportion of oil or
grease, after which the whole is stirred constantly
to mix it well together. Little by little the soda be-
comes incorporated with the grease, and soap forms
and floats on the surface in a compact layer, which
is then taken off and poured into molds where it con-
geals in thick square slabs. These slabs are after-
ward divided into cakes of a convenient size.

SOAP 103

*^ There are two kinds of ordinary soap, white soap
and marbled soap. The first is white throughout,
the second veined with bluish lines. For common
use marbled soap is preferable to the other. Be-
sides soda and grease or oil, soap of any kind always
contains a greater or less proportion of moisture
coming from the water in which it was boiled. Now,
white soap contains nearly half of its weight in
moisture, while marbled soap contains not quite a
third. Being richer in the ingredients that really
count, marbled soap is for that reason more econom-
ical.

** Resinous soap is a kind of soap that contains
resin instead of tallow or oil. This soap is of a yel-
low wax color, and its cakes are transparent on the
edges. It makes a great deal of lather on being dis-
solved in water, is very strong, and is good for wash-
ing clothes.

*^ Toilet soap is prepared from choice materials
and is perfumed with various aromatics embodied in
its substance.^'

CHAPTEE XIX

FIRE

»<

E do not know how man first procured fire.
Did he take advantage of some blaze started
by a thunderbolt, or did he kindle his first firebrand
in the crater of a volcano? No one can tell. What-
ever may have been its source, man has enjoyed the
use of fire from the earliest times ; but as the means
of relighting it if it went out were very imperfect or
even lacking altogether, the utmost care was taken
to maintain it, and a few live coals were always kept
over from one day to the next.

* ^ So calamitous would have been the simultaneous
extinction of the fires in all the dwellings that, in
order to guard against such a disaster, the priest-
hood took fire under its special protection. In
ancient Rome, many centuries ago, an order of
priestesses called Vestals was charged with the
guarding of the sacred fire night and day. The un-
fortunate one who let it go out was punished with
horrible torture: she was buried alive!''

**Did they really bury her alive for letting the
fire go outr' asked Jules.

**Yes, my boy. This terrible punishment inflicted
on the keepers of the fire shows you the importance
they attached to keeping at least one hearth alight so
that others could be kindled from it."

* * One of our matches that we buy at a cent a hun-

104

FIRE 105

dred/' said Claire, ^Svould have saved the life of
the careless Vestal."

**Yes, to abolish those barbarous severities it
needed only a match, a thing which unfortunately
was at that time unknown.

*^Many centuries passed before it was discovered
how to procure fire easily. In my young days, when
I was about your age, keeping coals alive to be used
for relighting the fire next day was still the rule in
the country. In the evening before the family went
to bed, the embers were carefully covered with hot
ashes to prevent their burning out and to keep them
alive. If, despite this precaution, the hearth was
cold next morning, some one had to hasten to the
nearest neighbor's to borrow some fire, that is to
say a few live coals, which were carried home in an
old wooden shoe to keep the wind from blowing them
away. ' '

^^But I should think the old wooden shoe would
have caught fire," said Emile.

^^No, for care was taken to put a layer of ashes
in first. I have told you how some children would
put a few ashes in the hollow of their hand, and on
the ashes lay live coals. They carried fire thus just
as you would carry a handful of sugar-plums.

*^The layer of ashes arrested the heat of the em-
bers and prevented its reaching the hand. Remem-
ber what I have already told you about the poor
conducting power of ashes, their refusal to transmit
heat, a characteristic they have in common with all
powder}^ substances. The little fire-borrowers knew
that well enough,"

106 THE SECRET OF EVERYDAY THINGS

' ' But who taught them to do it that way ! ' ' asked
Emile.

'^The great teacher of all things, necessity.
Caught without shovel or wooden shoe, some one of
them, knowing this peculiarity of ashes in arresting
heat, made use of the ingenious device I have de-
scribed, and his example was sooner or later followed
by others.

^^Fire-producing devices are, as a rule, based on
the principle that heat is generated by friction. We
all know that we can warm our hands by rubbing
them against each other. ' '

^'That's what T alwaj^s do in winter when my
hands are frozen from making snowballs," said
Jules.

*^That is one of the oldest illustrations of the
effect of friction, and I will add another. Hold this
round-headed metal button by the shank and rub it
briskly on the wood of the table; it will become
warm enough to produce a decided feeling on the
skin.''

Claire took the button, rubbed it on the wood of
the table, and then applied it quickly to her hand,
uttering a little cry of surprise and even of pain as
she did so.

' ' Oh, how hot the button is. Uncle ! ' ' she exclaimed.
^ ' If I had rubbed any longer I should have scorched
my hand. ' '

^ ^ It is by similar means that certain savage tribes
procured and still procure fire. They twirl very
rapidly between their hands a slender stick of hard
wood with its pointed end inserted in a cavity hoi-

FIRE 107

lowed in soft and very inflammable wood. If the
friction is brisk enough and the operation properly
carried out, the soft wood catches fire. This pro-
cess, I admit, would fail of success in our hands for
lack of skill. '^

*^For my part," said Marie, ''if I had nothing but
a pointed stick and a piece of wood with a hole in it
for lighting a fire, I should despair of ever manag-
ing it. ' '

"I should not even try it," Claire confessed, ''it
seems so difficult, although the button that I rubbed
came near burning me."

"A\Tiat would be impossible for us is mere play for
the natives of Australia. The operator sits on the
ground, holding between his feet the piece of wood
with the little hole, and twirling the pointed stick
rapidly between his hands he soon obtains a spark
with which he kindles a few dry leaves.

"Even in our o\\m country you may see, in any
wood-turner's shop, this friction process employed
successfully. To obtain the brown ornamental lines
on certain objects turned in a lathe, the operator
presses with some force the point of a bit of wood on
the piece in rapid rotation. The line thus impressed
by friction begins to smoke in a few moments, and
soon becomes carbonized.

"I pass on to other methods of producing fire.
Iron and steel, especially the latter, if rubbed against
a very hard stone give out sparks made by tiny
scales of metal that become detached and are suf-
ficiently heated to turn red and burn in the air.
Thus the scissors-grinder 's revolving stone, although

108 THE SECRET OF EVERYDAY THINGS

constantly moistened with water, throws out a
shower of sparks under the steel knife or other tool
that is being sharpened. In like manner the cobble-
stone struck by the horse's iron shoe emits sudden
and brilliant flashes.

^ ^ The common flint-and-steel apparatus acts in the
same way. It consists of a piece of steel that is
struck against the edge of a very hard stone called
silex or flint. Particles of steel are detached from
the metal and, made red-hot by the friction, set fire
to the tinder. This latter is a very combustible sub-
stance obtained by cutting a large mushroom into
thin slices and drying them, the mushroom being of
the kind known as touchwood, which grows on tree
trunks. ''

CHAPTER XX

MATCHES

*< AS tinder burns without flame, the glowing spark
jlV obtained with flint and steel before the inven-
tion of our matches did not suffice for obtaining fire ;
we had to have recourse to sulphur, which possesses
the invaluable property of bursting into flame at the
mere touch of a red-hot substance.

^ * Sulphur is so well known to you as to render any
description of it here unnecessary. It is found
especially in the neighborhood of volcanoes, where
it occurs in the soil, sometimes in masses free from
all admixture, sometimes in mingled masses of
sulphur and earth or stone. Man's work consists
merely in purifying the sulphur by melting it as it
comes from the mine.

**In the olden time matches were made of pieces
of hemp dipped at one end into sulphur. They were
lighted by having the sulphur-tipped end touched
either to a live coal that was kept glowing under the
ashes, or to a bit of tinder previously kindled by flint
and steel. Thus you see the mere lighting of a lamp
was a process not devoid of complications. First
the flint and steel must be struck together, at the risk
of bruising one^s fingers by an awkw^ard movement
in the dark; then, when the tinder had taken fire
after many attempts which often exhausted the

109

110 THE SECRET OF EVERYDAY THINGS

patience, it was necessary to apply the sulphur
match in order to obtain a flame.''

^*Our matches of to-day are much to be pre-
ferred,'' remarked Claire. *^A11 you have to do is to
strike them against the box cover or against the wall
or a piece of wood, no matter where, and the thing
is done: the fire burns."

*^This inestimable benefit of being able to obtain
fire without difficulty and on the instant we owe to
phosphorus, a substance discovered, as I have al-
ready told you,^ by a learned investigator named
Brandt, who lived in Hamburg two hundred years
ago. In attempting the impossible transformation
of baser metals into gold, he hit upon an elementary
substance until then unknown, and thus gave us the
self-igniting sulphur match with its tip of phos-
phorus.

^ ^ ' If you examine one of our common matches you
will see that the inflammable end is coated, first with
sulphur, and then, over this, with phosphorus, the
latter being colored with a red, blue, or brown
powder, according to the maker's fancy. Phos-
phorus by itself is yellowish and translucent like
wax. Its name means light-bearer. When it is
rubbed gently between the fingers in a dark place,
the fingers are seen to be covered with a pale light.
At the same time a smell like that of garlic is de-
tected; it is the odor of phosphorus. So inflam-
mable is this substance that it takes fire when heated
only a very little or when rubbed against any hard

1 See "Field, Forest, and Farm."

MATCHES 111

surface. Hence its use in the manufacture of fric-
tion-matches.

^' These are little sticks of wood — willow, poplar,
or spruce — wrought with the help of steel plates
pierced with holes ha\TJig sharp cutting edges
through which the wood is forced by powerful pres-
sure. Then these little sticks, held in position by
frames made for the purpose, are first dipped at one
end into melted sulphur. Over this first coating,
which is designed to feed the flame and give it suf-
ficient intensity to ignite the wood, must be laid a
second that will take fire by friction ; and this latter
coating is composed chiefly of phosphorus. On a
marble table is spread a semi-fluid paste made of
phosphorus, glue, very fine sand, and some coloring
matter. The matches, still held in position by the
frames just referred to, have their sulphur tips
touched for an instant to this inflammable paste, and
are then placed in an oven where the paste is al-
lowed to dry. Friction, aided by the fine sand in-
corporated in the paste, develops enough heat to
ignite the phosphorus; this in turn sets the sulphur
on fire, and from the sulphur the flame spreads to the
wood.

^'Phosphorus is a deadly poison, and therefore
matches must be handled with care, this precaution
extending even to the empty boxes that have held
them. Contact with our food might entail serious
consequences. Nevertheless this fearful substance
is found in all animal bodies. It is present in the
urine, whence Brandt was the first to extract it; it
occurs in meat, in milk, and above all in bones.

112 THE SECRET OF EVERYDAY THINGS

Plants also, especially cereals, contain it, and hence
it enters into the composition of flour and of bread. ' '

*^What!'' exclaimed Claire, ^^a substance so
frightful, a poison so violent, is found in milk,^meat,
and bread 1 ' '

^' Don't be alarmed, '^ her uncle reassured her.
**We run no risk whatever of being poisoned by
drinking a glass of milk or eating meat and bread.
The phosphorus there present does not occur by it-
self, but combined with other substances which de-
prive it entirely of all poisonous attributes and
render it useful, in fact necessary, to the strength of
the body. It is to be feared as a poison only in the
condition in which it is found in matches. I should
add in conclusion that the method adopted by Brandt
for obtaining phosphorus — namely, from urine — has
long since been abandoned. At the present time it is
extracted from the bones of animals.''

*^Then it is bones that furnish us with phos-
phorus?" said Jules.

^^Yes, bones are by an ingenious device made to
yield us phosphorus and, consequently, light and
heaf

CHAPTER XXI

WOOD AND CHARCOAL

OF wood used for fuel it is customary to dis-
tinguish two kinds, hard and soft. At the
head of the former class stand the different species
of oak, notably the common oak scattered all over
France, and the evergreen or holm oak peculiar to
the south. This last is called evergreen because it
does not shed its foliage in winter, but continues
green the year through. Among the soft woods are
the poplar, willow, plane-tree, and pine.

^'The way in which these two kinds of wood burn
is quite different in the two instances. Soft wood,
suitably dried, takes fire readily and gives much
flame with a heat that is quick but of short duration.
It is convenient for use in the kitchen, where it is
often necessary to obtain a prompt and intense heat,
for example in roasting fowl on the spit and in cook-
ing with the frying-pan. Furthermore, soft wood is
very useful for kindling other and less combustible
fuel, such as hard wood, coal, and charcoal. But for
use in open fireplaces, when it is desired to keep a
fire going all day long, soft wood is by no means
economical, because it bums up so quickly. The best
fuel in this case is oak, which bums slowly and yields
a large, compact mass of coals that retain their heat

113

114 THE SECRET OF EVERYDAY THINGS

for hours at a time, especially if care is taken to
cover them partly with ashes. '^

'^I have noticed the difference you speak of," said
Marie. ^^ Willow and poplar burn to ashes in a few
minutes, leaving hardly any coals; but oak gives a
fire that lasts and at the same time leaves a mass of
glowing coals. '^

^^If we had to keep up a fire with dry twigs and
willow splinters," remarked Claire, ^^we should be
kept busy all day throwing on wood, whereas three
or four sticks of oak last a long time."

Emile here interposed with a question. *^How is
charcoal made, ' ' he asked, ^ ^ such as is used for cook-
ingl"

'^Charcoal is made from wood," was the reply.
^'Its superiority to wood is that it bums almost
without smoke and without flame, a very valuable
quality where cleanliness is desired, as it is in our
kitchens. More than that, charcoal yields a heat that
is equable and lasting, thus dispensing with the need
of careful watching. The best charcoal is obtained
from the best wood, that is to say from oak, espe-
cially evergreen oak. I will now describe its mode of
manufacture as followed by charcoal-burners in the
heart of a forest.

^^Upon a plot of ground beaten hard and level
there is first built a sort of chimney made of logs
planted vertically in the soil, and around this chim-
ney the wood destined to be converted into charcoal
is piled in tiers, one on top of another, but with open-
ings left at the base for admitting air. The whole
is covered with a layer of earth and sod, leaving ex-

WOOD AND CHARCOAL 115

posed only the central chimney and the air-holes at
the base. Finally, the mass is set on fire by means
of dry brushwood. ''

^^I should think, '^ said Jules, ^'that the whole pile
would burn up and leave nothing but ashes, a dead
loss to all concerned. '^

*^By no means,'' replied Uncle Paul. ^^ Since air
can reach the burning mass only with difficulty, com-
bustion is slow and the wood is but half consumed.
Besides, if the fire should burn too briskly the attend-
ants would make haste to stop up with sod some or,
if necessary, all of the vents at the base of the pile.
As soon as the pile is thought' to be one mass of
glowing coals, the fire is smothered with earth and
the structure is left to cool off. When this process
is complete the work of demolition is undertaken,
and in place of wood in its primitive state there is
found nothing but charcoal. Some few fragments
there may be that are not thoroughly charred, and
they are recognized by their reddish color. They
are the half-burnt pieces we find now and then in
our charcoal."

^'I know them," said Claire, ^Hhey make such a
disagreeable smoke; and I always take them out of
the stove as quickly as I can and throw them into the
fireplace."

' ' That is right, ' ' returned Uncle Paul. ' ' And now
let us direct our attention to another kind of coal,
the coal that is dug out of the earth and that comes to
us from the coal-mines. Coal of this sort is of
vegetable origin, no less than the charcoal whose
mode of manufacture in the heart of the forest you

116 THE SECRET OF EVERYDAY THINGS

now understand. But charcoal-burners do not make
this other coal ; it is found all made in the bowels of
the earth, at great depths below the surface. '^

*'But how,'^ asked Claire, ^'can coal from deep
down in the earth come from vegetable matter grow-
ing only on the surface 1 ' '

**To explain that to you in full is out of the
question, because your knowledge is still too elemen-
tary; but I can at least give you some idea of the
natural processes involved.

*^Let us suppose the existence of great forests of
luxuriant growth, forests that man can never pene-
trate with his instruments of destruction. The trees
fall under the weight of years and go to decay at the
foot of other and younger trees, forming at last a
layer of matter half carbonized by the action of the
elements. One generation of trees succeeds another,
and the layer grows thicker, so that after centuries it
attains the thickness of a meter or more. Imagine
now a succession of violent earthquakes which break
up the surface of the earth, pushing up mountains
where before there have been plains, and making
plains where there have been mountains. Imagine,
further, that as a result of these changes of level the
sea is displaced and forced to forsake, wholly or
partly, its old bed for a new one; conceive of this
new sea as covering the shattered remains of old
forests with mud and sand that eventually become
hardened and converted into thick beds of rock ; and,
finally, picture to yourselves the sea as at last, in
consequence of still further upheavals of the earth's

WOOD AND CHARCOAL 117

surface, forsaking the new bed it had found for itself
and seeking still another, leaving behind it a conti-
nent of dry land. Thus you will have all the essen-
tial facts that you require in order to understand the
presence of coal in the interior of the earth.''

^^But those frightful upheavals that you speak
of,'' put in Jules, ^' those great changes that make
continents of seas and seas of continents — have they
ever really taken place?"

^^A science called geology," replied Uncle Paul,
^^ teaches us that these events actually occurred as I
have described them, but so long ago that man was
not yet in existence.

^ ' There was a time, for example, when this comer
of the globe that bears to-day the fair name of
France was composed merely of a few small islands
lost in a vast ocean. On these islets, which were
covered with lakes and volcanoes, there flourished a
luxuriant vegetation, the like of which is no longer
anywhere to be found except perhaps in the depths
of some tropical jungle. The very regions where
now grow beech trees and oaks used to bear immense
ferns, each balancing at the top of its tall stem a
graceful cluster of enormous leaves. These fern
trees constituted the greater part of somber, damp
forests which were never enlivened by the song of
birds and never heard the step of quadruped ; for as
yet the dry land was without inhabitants. The sea
alone maintained beneath its billows a population of
monsters, half fish, half reptile in form, their flanks
clothed in an armor of glittering scales. The re-

118 THE SECRET OF EVERYDAY THINGS

mains of that ancient vegetation, buried in the
depths of the earth by some stupendous cataclysm,
have become the coal-beds of to-day in which are still
discerned the admirably preserved outlines of leaf
and stalk. ^'

CHAPTER XXII

COAL AND COAL-GAS

<'TF I should take it into my head," Uncle Paul re-
X sumed, ''to begin my talk to-day in some such
fashion as this, 'Once upon a time there lived a king
and a queen,' and if I introduced into my fanciful
tale a wicked ogre greedy for human flesh and a good
fairy borne over the surface of the sea in a mother-
of-pearl shell drawn by red fishes, I am firmly con-
vinced that your attention would at once be riveted
to my account of the deeds done by king and ogre
and fairy, so that you would give me no peace until
the story was finished.

"Now, real things can otfer to your curiosity food
that is just as wonderful and that, moreover, feeds
the mind with useful knowledge. Coal, the history
of which I sketched in outline at our last talk, is one
example among a thousand.''

"It is very true. Uncle," said Marie, "that Cin-
derella or Bluebeard never interested me as does the
story you began to tell us about coal. Those little
islands that afterw^ard became France by changes in
the ocean-bed, those ancient forests which man has
never seen, but which to-day he finds transformed
into coal deep doA\m in the earth, those upheavals in
the surface of the earth, turning ever^^thing topsy-
turvy, all excite In me the liveliest interest^ and I

}19

120 THE SECRET OF EVERYDAY THINGS

should very much like to hear more about them."

*^Let us talk a little more, then, about coal. But
what could I select humbler in appearance and less
worthy of your attention than that black stone!
Nevertheless there are some most astonishing things
to be said about it. First of all, coal — black, dirty,
with no claim to distinction in its aspect — is own
brother to the diamond, the sumptuous gem that for
brilliance has no equal in all the world. The dia-
mond is made of carbon, and so is coal — the very
same substance in both. ' '

^ * The diamond made of carbon ? ' ' cried Claire, in-
credulously.

^^Yes, my child, of carbon and nothing else."

<<But— "

*^ There are no buts. Again I say the diamond is
made of carbon, but in a perfectly pure and crystal-
line form, which explains its transparency and
brilliance. I told you that coal had things to tell us
of a most marvelous nature. ' '

''I see now that it has," assented Claire.

^'Furthermore, this piece of black stone traces its
origin to remote ages when it made part of some
elegant tree such as you will nowhere find at present
unless perhaps in some tropical region enjoying an
abundance of heat and moisture."

''Then it must have come from one of those
ancient forests you told us about yesterday," said
Emile.

"Yes, and I can prove it to you. As a rule coal
occurs in shapeless masses which furnish no indica-
tion of their origin; but not infrequently there are

COAL AND COAL-GAS 121

found, in the cleavage between two layers, distinct
traces of carbonized vegetable matter having per-
fectly recognizable outlines. Certain coal-beds are
formed entirely of leaves heaped up and pressed to-
gether into a solid block, and still preserving, despite
their conversion into coal, all the details of their
delicate structure. These relics of a plant life as
old as the world, wonderful archives which tell us
the earth's history, are so well preserv^ed that they
enable us to recognize the carbonized plants with the
same certainty we feel in recognizing living plants.
Yesterday, while our winter supply of coal was being
put in, I chanced to notice in the bin some of those
venerable relics I have just been speaking about, and
I put them aside to show to you. Here they are. "

^^Oh, what beautiful leaves!'' exclaimed Marie.
'^How nicely they are attached to the black surface
underneath! One would say they had been cut out
of very thin sheets of coal." She stood lost in
thought before these remains of forests so extremely
old as to antedate all animal life.

*^When the plant life was flourishing which you see
represented here," went on Uncle Paul, ^Hhe earth
was covered with a vigorous growth of vegetation
unexampled in our o^^^l time. This vegetation,
buried far underground by changes in the earth's
surface, and carbonized in the course of a long series
of, centuries, has become transformed into enormous
masses of coal which constitute the soul, so to speak,
of modern industry. For it is coal that moves the
railway locomotive, with its line of heavy cars ; it is
coal that feeds the furnaces of factories; it is coal

12£ THE SECRET OF EVERYDAY THINGS

that enables the steamboat to brave wind and storm ;
and it is coal that makes it possible for us to work
the various metals and manufacture our tools and in-
struments, our cloth and pottery, our glassware and
all the infinite variety of objects necessary to our
welfare. Are you not filled with wonder, my chil-
dren, as I am, that long before man's appearance
upon earth everything was prepared for his recep-
tion and for providing him with the things essential
to his future industry, his activity, his intelligence!
Are you not impressed by this vegetation of prehis-
toric times which stored up in the bowels of the earth
those precious deposits of coal that to-day are
brought to light and made to move our machines and
become one of the most active agents of civiliza-
tion?"

^^From now on,'' replied Marie, *' whenever I put
a shovelful of coal on to the fire, I shall think of that
ancient plant life which gave us this fuel. ' '

^'Nor is the whole story of coal told yet," Uncle
Paul went on. ^^ Besides heat, coal gives us light.
Cities are illuminated by street lamps which bum no
oil and have no wick, but emit a simple jet of gas
which, on being ignited, produces a magnificent white
flame. ^ This gas is obtained by heating coal red-hot
in great air-tight ovens. Pipes laid under ground
conduct the gas from the gas-works to all parts of
the city and distribute it to the street lamps. At
nightfall the burner is opened and the gas flows, tak-

1 Only older readers will recall this method of street-lighting,
which has long since been superseded by electric lamps of various
kinds, — Translator,

COAL AND COAL-GAS 123

ing fire at a little hand-lantern with exposed wick,
whereupon the flame bursts forth.

**Wliat remains in the ovens after the manufact-
ure of illuminating gas is a modification of coal
known as coke, an iron-gray substance with a dull
metallic luster. Coke develops much more heat than
the best wood-charcoal, but is difficult of combustion
and in order to burn well must be heaped up in con-
siderable quantity and have a good draft. For do-
mestic heating it is used in stoves and, still oftener,
in grates. It is superior to coal in giving forth no
smoke, thus being cleaner.

^* Together with gas there is produced in the ovens
in which coal is heated a black and sticky substance
called coal-tar. From this horrible pitch, which one
cannot touch mthout soiling one's hands, modern
invention knows how to extract something in the
highest degree fresh and beautiful and fair to look
upon. As we have seen, the splendid colors of our
silks and cottons, the rich and varied tints of our
ribbons — all these we owe to dyestuff s obtained from
coal-tar. Common coal, therefore, far from im-
pressive though it is in appearance, is linked with the
most dazzling splendors this world can produce: on
the one hand with the diamond, with which it is one
in essence, and on the other with tho flowers of the
field, whose delicate coloring it imitates and even
surpasses/^

CHAPTER XXIII

COMBUSTION

^ ' T ET us light a shovelful of charcoal in the kitchen
i J stove. The charcoal catches fire, turns red,
and is consumed, while at the same time producing
heat. Before many minutes there is nothing left but
a handful of ashes weighing but a trifle compared
with the quantity of charcoal burned. What, then,
has become of the charcoal? *'

**It has been consumed,'' answered Jules; ^*it is
burnt up.'*

^^ Agreed. But being consumed — does that mean
being reduced to nothing? Does charcoal, when
once it has been burned, become nothing at all, abso-
lutely nothing ? ' '

*^It has turned to ashes,'' Jules replied.

^*You haven't hit it yet, for the ashes left after
combustion amount to very little compared with the
quantity of charcoal consumed. ' '

**Your question, dear Uncle," Marie here inter-
posed, ''puzzles not only Jules, but me too, very
much indeed. If there -is n't any more than a hand-
ful of ashes left after the charcoal is burnt up, I
should say the rest has been destroyed. ' '

''If that is your opinion I would have you know
that in this world nothing is 'ever entirely destroyed,
not a particle of matter ever becomes nothing after

124

COMBUSTION 1^5

having been something. Try to annihilate a grain
of sand. You can crush it, convert it into im-
palpable powder; but reduce it to nothing — never.
Nor could the most skilful of men, men equipped with
more varied and more powerful appliances than
ours, succeed any better. In defiance of every
exertion of ingenuity or violence the grain of sand
will still continue to exist in some form or other.
Annihilation and accident, two big words that we use
at every turn, really do not mean anything. Ever}^-
thing obeys laws : everything persists, is indestruct-
ible. The shape, aspect, appearance, changes; the
underlying substance remains the same.

''So the charcoal that is burned is not annihilated.
True, it is no longer in the stove ; but it is in the air,
dissipated and invisible. When you put a lump of
sugar into water the sugar melts, is disseminated
throughout the liquid, and from that time ceases to
be visible even to the keenest scrutiny. But that
sugar has not ceased to exist. The proof is that it
communicates to the water a new property, a sweet
taste. Furthermore, nothing stands in the way of
its ultimate reappearance in its original form. All
we have to do is to expose the sweetened water to
the sun in a saucer; the water will disappear in
vapor and the sugar remain.

''Charcoal behaves in like manner. In burning
it is dissipated in the air and becomes invisible.
This dissipation is called combustion. What do we
do when we wish to make the fire burn faster? With
the bellows we blow air on the fuel. With each puff
the fire revives and burns brighter. The live coals,

1^6 THE SECRET OF EVERYDAY THINGS

at first dull red, become bright red and then white-
hot. Air breathes new life into the bosom of the
burning mass. If we wish, on the other hand, to pre-
vent a too rapid consumption of fuel, what do we do!
We cover the fire with ashes, thus keeping out the
air. Under this layer of ashes the live coals retain
their heat and remain red for a long time without
being consumed. Thus it is that a fire in a grate is
maintained only by the constant admission of air,
which makes the coal burn ; and the faster it burns,
the greater the amount of heat given off. ' '

* ^ Then that must be why the stove gets so hot when
it roars,'' remarked Claire. *'Air is let in between
the bars of the grate and then goes roaring through
the red-hot coals. But if the air is prevented from
circulating by closing the door of the ash-pit, the
heat subsides at once."

^^When the air is impregnated mth carbon it ac-
quires new properties, just as water does on becom-
ing charged with salt or sugar. This new element is
an injurious substance, a harmful gas, all the more
to be feared because it does not reveal its presence,
having neither smell nor color. We do not take note
of it any more than we do of ordinary air.

^'But let any one breathe this formidable gas, and
immediately the brain becomes clouded, torpor
supervenes, strength fails, and unless help arrives
death soon follows. You have all heard of unfortu-
nate persons who inadvertently — sometimes, alas!
designedly — have met death in a closed room by
lighting a brazier. The fact that the air becomes
impregnated with the dissipated carbon from the

COMBUSTION m

burning charcoal explains these lamentable acci-
dents. Inhaled even in a small quantity, this deadly
gas induces first a violent headache and a general
sense of discomfort, then loss of feeling, vertigo,
nausea, and extreme weakness. If this state con-
tinues even a very little while, life itself is en-
dangered.

^ * You see to what a risk charcoal exposes us when
the products of its combustion do not escape outside
through a chimney, but spread freely indoors, espe-
cially if the room is small and tightly closed. Under
these conditions you cannot be too distrustful of
a brazier. Whether burning brightly or half ex-
tinguished, whether covered with ashes or not, these
embers exhale a deadly gas which does not announce
its presence by any sign that we can recognize, but,
like a traitor, always takes us by surprise. Death
may occur even before danger is suspected.

** Again, it is very imprudent to close the damper
of a bedroom stove for the sake of maintaining a
moderate heat during the night. The stovepipe
being closed by the damper, there is no longer any
outlet for the products of combustion, which are sent
out into the room and asphyxiate the sleepers, so
that they pass from life to death without even wak-
ing up. ^

''If the apartment is small and without openings
for changing the air, a simple foot-warmer is enough
to cause a headache and even lead to more serious
results. ' '

1 With proper ventilation, as the author might have added, this
danger is greatly lessened. — Translator.

IM THE SECRET OF EVERYDAY THlNGB

^^Now I understand/' said Marie, ^Hhe headaches
I sometimes have in winter when I am sewing in my
little room, all shut up with a foot-warmer under
my feet. It was the burning charcoal that gave me
those headaches. That is a good thing to know, and
I will be careful in future/'

*^Be just as careful with charcoal when you are
ironing. Keep the heater for the irons under the
chimney or in a well-ventilated place, so that the
dangerous exhalations from the embers may be car-
ried out into the open air. Those who do ironing
often complain of an uncomfortable feeling which
they attribute to the smell of the iron, whereas it is
due to the deleterious gas given off by the burning
charcoal. It can be avoided by keeping the heaters
under a chimney or in a current of air that drives
away the injurious gas.''

CHAPTER XXIV

HEATING

** T HAVE told you how man has possessed fire ever
JL since the earliest times. The first fireplaces for
preparing food and furnishing protection from cold
consisted of armfuls of fagots burning between two
stones, either in the open air or in the middle of the
hut. This rude method of domestic heating still pre-
vails among many savage tribes. On flagstones in
the middle of the dwelling smolder a few firebrands,
the smoke escaping as best it can through some
chance cracks and crannies in the roof. Indeed, if
you wish to view this primitive method of making a
fire, you need not go to distant countries beyond the
reach of the benefits of civilization. In certain
mountain cantons of France the fireplace is still to
be seen in the form of a large flat stone in the middle
of the room, the walls and rustic furnishings of
which have become coated by the action of smoke
with a brilliant Varnish as black as shoe-polish. The
cracks in an imperfectly fitted roof furnish the only
outlet for the products of combustion."

*^The family must be nearly smothered to death,"
said Claire, ^Svhen the fire smokes in the middle of
one of those chimneyless houses. Why don't they
make a fire like ours ? ' '

^^ Chimneys are a rather recent invention, and in

129

130 THE SECRET OF EVERYDAY THINGS

those remote mountain villages habit preserves old
traditions indefinitely. Antiquity in its period of
highest refinement knew absolutely nothing of our
common chimney. A striking proof of this is given
us by a celebrated city, Pompeii, which was buried
in the year seventy-nine of our era under a bed of
volcanic ashes thrown up by Mount Vesuvius. Its
houses, after having been buried for eighteen cen-
turies, are exhumed to-day by the miner's pick and
come to light again as they were when overwhelmed
by the volcano. Not one of them has a chimney.
In the old Roman town people warmed themselves
with burning charcoal placed in a large metal vessel
on a bed of ashes. This portable fireplace was put
in the middle of the room to be warmed, without the
slightest reference to air currents or the escape of
harmful gases engendered by the burning charcoal.
And even in our ovna time, in Italy and Spain, simi-
lar open braziers are used.''

*'I should think," said Marie, ^*that there would
be danger of accidents, or at least that the people
would have headaches due to the burning charcoal."

**The mildness of the climate, which does not call
for air-tight houses, permits this vicious mode of
heating in Spain and Italy; but braziers would be
very dangerous in our homes, where windows and
doors must be carefully closed during the winter.
Unchanged air impregnated with the deleterious
gases from combustion would soon lead to discom-
fort and even asph}^ia.

*'The first chimney-places for domestic use men-
tioned in history date from the fourteenth century.

HEATING 131

Disproportionately large, very costly, burning whole
trunks of trees for fuel, these chimney-places were
at first constructed without any knowledge of how
to economize heat. Immense fires were built, but
with no resulting warmth proportioned to the fuel
used. The subject of draft was not in the least un-
derstood, and it was not until the end of the last
century that there was any clekr perception of the
truth that draft in a fireplace is caused by the dif-
ference in temperature between the air of the chim-
ney-place and that outside.

**I will now call your attention to something you
have witnessed a thousand times in winter when you
sit around the red-hot stove. Light a piece of paper
and wave it to and fro over the hot stove. You will
see the burnt particles rise, whirling and ascending
sometimes as high as the ceiling. Why do they rise
thus? They do so because they are carried by the
air which, being heated by contact with the stove,
becomes lighter and forms a rising current. These
light fragments of burnt paper show us the upward
flow of the air just as pieces of floating wood indi-
cate the current of water. Thus air that is heated
becomes light and rises.

• ^^ There we have the explanation of the draft in a
fireplace. When the fire is lighted in the fireplace,
the air contained in the chimney is warmed, becomes
lighter, and rises. The hotter the air and the higher
the column of heated air, the more powerfully it
rushes upward. At the same time that the hot air
rises, cold air, which is heavier, flows toward the
fireplace, accelerates combustion, becomes warm in

13g THE SECRET OF EVERYDAY THINGS

its turn, and joins the ascending column. In this
way there is set up a continual current from the
lower to the upper part of the chimney. To this in-
cessant flow of air through the fireplace we give the
name * draft.'

^^The prime requisites for a good draft can now
easily be seen. First, the chimney must be entirely
filled with hot air. If the channel is too large there
is established at the top a descending current of cold
air which mixes with the warm ascending current,
slackens its course, and even makes it flow back into
the room. Then the chimney smokes. A remedy
for this is to make the chimney smaller at the top or
else cap it with a sheet-iron pipe.

^^Our chimneys are generally too large. Their
faulty construction is necessitated by the method
frequently employed for cleaning them. When a
poor child of Savoy, all begrimed with soot, worms
his way up the chimney by dint of much scraping of
elbows and knees, in order to sweep the soot from the
inner surface of the walls, the passage must be large
enough to admit his body, even though the draft
suffer in consequence. But if the sweeping is done
in a more suitable manner with a small bundle of
brushwood let down from above by a cord, there is
no reason why the chimney should not be as narrow
as may be necessary for a perfect draft.

^' Often, too, the lower opening, the one from the
chimney into the room, is too large. Then there
enter the channel at the same time hot air from the
central part where the fire is burning and cold air
from the vacant lateral parts. This cold air

HEATING 133

necessarily lessens the draft by mixing with the hot
air and lowering its temperature ; or it can even blow
the smoke back into the room.

**As far as possible only hot air should enter the
chimney, all cold air sucked in by the draft being
made to traverse the mass of burning fuel before
passing into the ascending flue. To this end, in
properly constructed fireplaces, the inner opening is
narrowed by making the enclosing walls of the fire-
place run obliquely inward so that most of the air
sucked in by the draft passes through the burning
fuel and becomes warm.

^^The slanting walls serve still another useful pur-
pose : they send back into the room a part of the heat
that would not other\\^se be reflected. To increase
their efficacy in this respect they are lined with
glazed tiles, which by their polish reflect a great part
of the heat.

^* Finally, the top of the chimney should be
equipped in such a manner as to keep out any gust of
wind that might else go whistling down toward the
fireplace and thus drive back the smoke. To this
end the chimney is capped either with a chimney-pot,
which offers obstruction to the inflow of outer air, or
with a sheet-iron hood that turns with the wind and
always points its opening to the leeward.

^^On account of the great volume of air con-
tinually passing through its Avide mouth, a fireplace
gives to a room excellent ventilation, a condition in-
dispensable to health in our close dwellings ; but its
utilization of heat is sadly defective, so far as warm-
ing is concerned, because the air heated by passing

134 THE SECRET OF EVERYDAY THINGS

through the fire is discharged into the outer at-
mosphere with no benefit to any one.

^^It is just the opposite with stoves: they warm
well, but they renew the air of a room very im-
perfectly. They warm well because the whole of
their heated surface, that of the sheet-iron pipe as
w^ell as that of the stove itself, is in contact with the
air of the room. Cast-iron stoves furnish quick and
intense heat, but cool off as quickly if the fire dies
do^\ai. Terra-cotta stoves, whether glazed or not,
heat more slowly, but their action is more contin-
uous, more gentle, more even; they retain their
warmth a long time after the fire is out. The
Swedes and the Eussians, in their rigorous climate,
use enormous brick stoves occupying an entire wall
of the room. The smoke and other products of com-
bustion, before escaping out of doors, circulate
through this mass of masonry by numerous channels.
A fire is lighted in the morning and left to burn for
several hours; then, when the wood is all converted
into glowing coals, every outlet is closed, and that
suffices to maintain a gentle heat in the room until
night, provided only the glacial outside air be not
admitted. But this mild and equable temperature
is secured only at the sacrifice of the purity of the
atmosphere, w^hich cannot be renewed in the tightly
closed room.

^ ' Our stoves have the same fault : they do not re-
new the atmosphere of a room well because they con-
sume for the same amount of fuel much less air than
a fireplace. In a stove, in fact, all the air that enters
is used up in burning the fuel; in an open fire, on

HEATING 135

the contrary, much air is drawn in that does not pass
through the burning fuel, but escapes outside with-
out having taken part in the act of combustion.

^* Besides the disadvantage of furnishing poor ven-
tilation, the cast-iron stove has still another defect.
The intense heat that it throws out dries the air to
such an extent as to make it unpleasant to breathe.
The great thirst one feels near a very hot stove has
no other cause. This dryness can be remedied by
placing on the stove a vessel full of water, which in
evaporating gives suitable humidity to the air. Fi-
nally, the various kinds of dust floating in the air
burn on coming in contact with the red-hot stove,
and give rise to disagreeable emanations. In short,
if the stove is the best heating apparatus in respect
to easy installation, economy of fuel, and utilization
of heat, it is one of the most faulty from a hygienic
standpoint, especially in a small room filled with
many people, ''

CHAPTER XXV

LIGHTING

*^fTlHE crudest method of lighting I have ever seen
A is to be found in certain out-of-the-way corners
of our mountain districts. Under the mantel of an
immense fireplace there stands, on one side, a box of
salt, kept dry 'by the heat of the fire, while on the
other projects a large flat stone on which in the even-
ing, with true economy, resinous splinters from the
trunk of a fir-tree are burnt; and that is the only
light, the only lamp, in the dwelling. By the light
of this red and smoky flame the housewife prepares
the soup and pours it into the porringers for the
family returned from their labor in the fields, while
the grandmother, silent in her big arm-chair, plies
the spindle with her lean fingers. ' '

*^A common oil-lamp,'' said Claire, ** would be far
preferable to that little fire of resinous wood. ' '

^^I do not deny it,'' replied Uncle Paul; ^^but oil
costs money, and a few little splinters of fir cost
nothing. ' '

^^But that pitch-pine torch only gives light right
round the fireplace. For going at night from one
room to the next some other kind of light is needed. ' '

^^They have the iron lamp, in which a cotton wick
inserted in a sort of socket burns grudgingly a few
drops of nut oil."

136

LIGHTING 137

^*That must give a very poor light — not so good as
a candle, even the kind that makes such a horrid
smell. ' ^

*'What are those bad-smelling candles made of,
Uncle Paul?'' asked Emile.

^^They are made of either mutton or beef fat,
which we know by the name of tallow. ' '

^' There are others, of a beautiful white, that are
not greasy to the touch and have hardly any smell. ' '

^^ Those are tapers, or wax-candles, as they are
called, and they are far superior to common candles,
although made from the same material, tallow. It is
true that the tallow destined for tapers undergoes
thorough purification, which removes its disagree-
able odor and its oil. The first step in this process
is the boiling of the tallow in water to which lime has
been added. Next there is called into service a pow-
erful drug, oil of vitriol, which takes away the lime
as soon as it has acted sufficiently. Finally, the
material under treatment is subjected to strong
pressure which squeezes out and gets rid of the oily
ingredient. After passing through these various
stages the tallow is no longer what it was. It has no
smell, or hardly any; its consistency is firm, its
color a perfect white. In this new state, which is
very different from the first, it is no longer called
tallow but stearin.

'^The notable improvement I have just described,
which was destined to give us the odorless taper with
its white flame in place of the foul-smelling, smoky
tallow-candle, dates from the year 1831.

^'Tapers, or wax-candles, are made in molds, which

138 THE SECRET OF EVERYDAY THINGS

are of metal and open at their base into a common
reservoir, the use of which I will explain presently.
Through each mold, running from end to end, passes
a wick, which is fastened at the bottom by a small
wooden pin, and at the top by a knot that rests on
the little central opening of a conical cap. After
the molds have been placed in position, with their
pointed ends downward and their bases upward, the
melted stearin is poured into the reservoir, whence
it runs into the several molds. Nothing more re-
mains to be done except to bleach and polish the
candles. They are bleached by exposure to the sun-
light for some time, and polished by rubbing with a
piece of cloth.

**Oil, which I will speak of in detail later, is also
used for lighting. There are several inferior kinds
commanding so low a price as to permit of their
use. Those in most common demand for lighting
are rape-seed oil, colza oil, and nut oil. They are
burned by the use of a woven cotton wick which
soaks up the liquid at its lower end and brings it
drop by drop to the flame.

^'If the candle is allowed to burn fully exposed to
the air, with no protecting glass chimney to regulate
and increase the draft, the flame is dim and smoky,
a part of the oil, decomposed by the heat, being lost
in smoke or collecting in the form of snuff on the in-
candescent part of the mck. To bum this smoke,
this carbon, and thus obtain a brighter light, a good
draft must be generated, as in fireplaces and stoves,
so as to utilize to the full the fuel that feeds the
flame. This is attained by m'eans of a glass chimney

LIGHTING 139

enclosing and surmounting the flame, allowing cold
air to enter at the bottom and hot air to escape at the
top. Only on this condition do lamps, of whatever
sort, give a good light.''

**I thought," said Marie, '^that lamp-chimneys
were only to protect the flame from puffs of air. ' '

' ' Chimneys do indeed protect the flame from puffs
of air that might make it flicker and go out, but they
also fill another office no less useful: they generate
a draft without which combustion would be imper-
fect and the light dim. If you remove the chimney
you will notice that the flame immediately becomes
smoky and dim; put the chimney on again, and the
flame will instantly recover its vigor and clearness.
It is the same with the lamp as with the stove : with-
out a sufficiently long pipe to create a draft, or, in
other words, to draw in air to the very heart of the
fuel, the stove would burn badly and give out little
heat ; and without the glass chimney bringing to the
wick a continual stream of fresh air the lamp would
make but poor use of its oil supply and would give
only a faint light.

*'The chimney is especially indispensable with
lamps that burn kerosene, a liquid very much used
at the present time for lighting. The lamp hanging
from the ceiling of this room to give us light in the
evening is filled with kerosene. You must have
noticed the great difference it makes with the lighted
wick whether the chimney is on or off."

*^That difference has always struck me," Marie
replied. ^'Before the chimney is on the flame is red,
very smoky, and gives hardly any light; but as soon

140 THE SECRET OF EVERYDAY THINGS

as the chimney is put on, the smoke disappears and
the flame turns a very bright white. Without its
chimney the lamp would not give much light and
would fill the room with black smoke."

^^In kerosene lamps the air necessary for combus-
tion comes through a number of little holes in the
metal disk that supports the chimney. If these holes
become obstructed with the carbonized refuse of the
wick, the draft works badly and the lamp smokes.
Then sometimes, ignorant of this detail, you are lost
in conjecture as to the cause of the wretched light
you are getting. The wick is badly trimmed, you say
to yourself, it is too long or too short, there is not
enough oil, or there is too much. You try this and
that remedy, all to no purpose ; the lamp still smokes.
The right remedy is nevertheless very simple: it is
only to take off the metal disk through which the
wick runs, and with a brush thoroughly to clean the
little holes with which it is riddled. These openings
clean, the air once more comes freely to the flame,
a draft is created without any obstacle, and the lamp
burns as brightly as ever.''

CHAPTER XXVI

KEROSENE OIL.

^'Tli THERE does kerosene come fromf asked
V y Claire. ''Is it a kind of oil something like
olive oil and nut oil ? "

' ' Notwithstanding the name of oil generally given
to it/' her uncle replied, "kerosene has nothing in
common with real oils. These are extracted from
certain kinds of fruit, the olive for example, or from
certain seeds like nuts and the seeds of flax and rape.
Kerosene has no such origin ; it is found ready-made
in the bow^els of the earth where certain stones are
impregnated with it and let it ooze out drop by
drop. The word petroleum (another name for it)
alludes to this mineral origin, for it signifies stone-
oil '^

' ' Stone-oil ! ' ' exclaimed Jules. ' ' I have never seen
stones that let anything like oil ooze out of them.''

' ' Nevertheless there are some, and in a good man}^
countries, too. I have already told you the history
of pit-coal.^ You know that it comes from prehis-
toric vegetation buried to a great depth by the cata-
clysms which earth and sea have undergone. This
coal, when heated without exposure to the air, gives
the illuminating gas that burns w^ith a white flame
superior in brightness to the light of our best lamps ;

1 See " Field, Forest and Farm."

141

142 THE SECRET OF EVERYDAY THINGS

it also yields coal-tar, which contains in large quan-
tities certain inflammable liquids, mineral oils closely
resembling petroleum. Layers of vegetable matter
buried by convulsions of nature in the bowels of the
earth, and converted into something like coal, have
managed to undergo in one way or another the kind
of decomposition accomplished in our gas-works.
Thence have come natural tar, bitumen, black pitch,
which the miner encounters in his excavations;
thence also comes the inflammable gas which in vari-
ous countries escapes from fissures in the ground
and serves as an inexhaustible supply of fuel; and
thence too we derive the liquid fuel designated by
the name of petroleum. So heat from coal and light
from petroleum are both a heritage coming down
to man through centuries from the ancient vegetation
of the world. ' '

*^You speak," said Marie, '^of the supply of fuel
in decomposed vegetable matter buried in the in-
terior of the earth. Does this supply furnish light
and heat?"

^^Most assuredly it does. There issues from it an
inflammable gas, a gas that burns with an intense
heat. Such supplies of natural gas are not rare in
oil-fields, as for instance around Lake Ontario in
North America. The inflammable gas escapes
through crevices in the rock, in the soil, and even in
the bed of the lake itself. It catches fire at the ap-
proach of any lighted object and, where the volume
of accumulated gas is large enough, sends forth long,
brilliant flames that even heavy rains sometimes fail
to extinguish. The spectacle is wonderful beyond

KEROSENE OIL 143

description when these jets of fire burst forth from
the very bosom of the lake and dart hither and
thither over the liquid expanse. In winter the effect
is still more remarkable. Then around each gas-jet
an ice chimney several decimeters long forms and
takes the shape of a huge crystal candelabrum, at the
top of which blazes the flame. The people in the
neighborhood make use of this reservoir of natural
gas : it is conducted to their dwellings through pipes,
and there it is burned in the fireplace for cooking or
in gas-burners for lighting. One of these burners
gives as much light as four or five candles com-
bined.''

"Those jets of flame must be very odd," remarked
Emile, "especially when they come out of the water;
but Lake Ontario is a long way off, and I shall never
see them."

"Without going so far as Lake Ontario," his un-
cle assured him, "you can see flames bursting out of
the water in the nearest ditch. Choose one abound-
ing in black mud made of decayed leaves, and stir
that mud with a stick. Big bubbles of gas will rise
and show themselves, bladder-like, on the surface of
the water. W.ell, if you hold a piece of lighted paper
near one of these bladders, the gas will catch fire,
producing a slight explosion and giving a verj^ feeble
light which would be invisible in the full glare of the
sun, but can easily be seen at nightfall or even in the
shade. This inflammable gas comes from vegetable
matter decaying under the water, just as the inflam-
mable liquid petroleum has its origin in vegetable
refuse buried in the depths of the earth.

lU THE SECRET OF EVERYDAY THINGS

**The same gas also escapes from coal, as is only
natural, since coal is formed from the remains of
ancient vegetation in the same way that black ditch-
mud is made principally of decayed leaves. Some-
times the subterranean excavations pushed to great
depths for extracting the coal become filled with this
inflammable gas. If a workman carelessly brings
his lantern near this formidable substance — which
gives no warning of its existence, as it is invisible
and has no odor — a terrible explosion takes place,
the mountain is shaken to its foundations, the scaf-
folding of the galleries falls down, and hundreds of
people perish at such a depth, alas, that no succor
is possible. Miners call this dangerous coal-mine
gas ^ fire-damp.^

^'Around the Caspian Sea these fountains of fire,
as we may call them, are numerous. All you have to
do is to stir the earth a little way down and hold a
light near the place, when instantly flames will spring
up that will burn indefinitely. One of these foun-
tains, that at Baku, is the object of superstitious
reverence on the part of a religious sect, that of the
Guebers or fire-worshipers. A magnificent temple
encloses it. The inflammable gas gushes out through
the cracks in the walls, from the summit of the
vaulted roof, from the tops of the columns surround-
ing the edifice, from the very ground of the sanctu-
ary, and from the entrance door. If a torch is ap-
plied, all these jets of gas catch fire in the twinkling
of an eye and the temple is enveloped in a splendid
curtain of flame. ' '

^ * That would be better worth seeing, ' ' said Claire,

KEROSENE OIL 145

^^than the inflammable bladders on the surface of a
muddy ditch. But unfortunately, as Emile has al-
ready remarked, it is rather too far away. ' '

^^I hope I have said enough," Uncle Paul resumed,
^'to show you that the presence of a combustible
liquid in the bowels of the earth has nothing in it that
cannot be easily explained. Coal, inflammable gases,
petroleum, all three have a common origin in the
ancient vegetation of the globe buried and decom-
posed underground.

^^Now let us talk about kerosene. North America
furnishes most of it. Excavations similar to our
wells are carried to a greater or less depth, and
through the walls of these excavations the oil oozes,
collecting little by little at the bottom as water does
in our ordinary wells.

^^ Kerosene has an oily appearance, but is easily
distinguished from oil by this peculiarity: whereas
oil makes a translucent blot on paper and does not
go away, kerosene makes a blot similar in appear-
ance but disappears with heat without leaving any
trace. That is because kerosene evaporates, while
oil remains. Furthermore, the smell of kerosene is
strong, penetrating, and somewhat like that of the
tar that comes from our gas-works.

^ ' The great inflammability of kerosene is a source
of serious danger, which it is important to under-
stand in order to ex-ercise the prudence called for in
handling this liquid. If you spill ordinary oil on the
ground and hold a piece of lighted paper near it, you
will not succeed in making it catch fire. Do the
same with kerosene and it will take fire more or less

146 THE SECRET OF EVERYDAY THINGS

quickly according to its quality. If it catches fire
instantly it is a very dangerous liquid and should be
used as little as possible, if one does not wish to be
exposed to the risk of serious accidents. But if it
takes fire with some difiiculty, it can safely be used
in our lamps. The best kerosene is the one that is
slowest in catching fire. ''

^^I should have thought, on the contrary,*' said
Marie, *'that the best would be the one that catches
fire the easiest."

'^It seems so to you because you overlook the
danger attending a too high degree of inflammabil-
ity. Suppose you are carrying a lamp filled with
ordinary oil; you stumble and fall, and the oil, to-
gether with the lighted wick, is dashed against your
clothing. What is the result? Nothing very seri-
ous. The oil spilt, being unable to catch fire even
close to the wick, will soil your clothes, it is true,
but at least you will not be burned. What a fright-
ful risk you run, on the contrary, if the lamp is filled
with kerosene, which takes fire so easily! Your
face and hands are splashed with the terrible liquid,
your clothes are soaked with it, and instantly you are
all on fire and in imminent danger of being burned
alive. ' '

**0h, goodness gracious ! if that should really hap-
pen to one of us!*'

^*If that should happen to one of you either with
kerosene or with any other inflammable liquid, such
as alcohol or ether, the first thing to do would be to
keep your presence of mind and not run about dis-
tractedly, this way and that, frightened out of your

KEROSENE OIL 147

wits: for with Your clothes flvino: in the wind thus
created you would only make bad worse by fanning
the flames. You should snatch up the first thing you
can lay hands on, carpet, table-cloth, shawl, or cloak,
and wrap yourself snugly in it so as to stifle the fire ;
you should wind it around your body very tightly
and roll on the floor while waiting for some one to
come to your aid.'^

^^Who can flatter himself,'^ said Claire, ^'that at
such a time he will preserv^e his presence of mindT*

* * You must do your best. Life may depend on it. ^'

*^ Would it not be well,'' asked Marie, ^^to have
nothing whatever to do with this dangerous liquid?"

*^No, indeed, because we have nothing better for
lighting purposes, and with a little prudence all
danger is avoided. In the first place, we should use
only kerosene that catches fire with difficulty when
tested by pouring a little on the ground and applying
a lighted match. Also, the supply should be kept in
a tin can and not in a glass bottle, which might get
broken; and when a lamp is filled it should be done
at a distance from the fire. Finally, it is advisable
to use this liquid as little as possible for hand-lamps,
lamps that are carried from place to place as we
carry a candle; it should be reserved for stationary
lamps, those fastened to the wall or hanging from
the ceiling and not likely to be touched after they
are once lighted. In that way the inflammable liquid
is not in danger of being spilt over us."

'^ These precautions make me feel safer," Marie
rejoined; *'but I know enough now to see that Avith
kerosene prudence must never be forgotten."

CHAPTER XXVII

GLASS

N CE upon a time, so the story goes, some sailors
overtaken by bad weather landed on a desert
shore and lighted a big fire to dry and warm them-
selves and pass the night. There being no wood on
this sandy coast, they made their fire of dry seaweeds
and grass. The furious wind caused their fire to
burn fiercely, and, behold, the next morning the
sailors were greatly astonished to find in the midst
of the ashes sundry lumps of a substance as hard as
stone but as transparent as ice. If they had seen
this substance at the water's edge, and in winter,
they would certainly have taken it for ice, but, raking
it out from under the ashes, they could not escape
the conclusion that it was something else."

^^And what was it?" asked Claire.

**It was glass, that precious substance that to-day
gives us our window-panes, which enable us to keep
our houses warm without excluding the daylight.
The sailors scrutinized closely the deposit left after
their fire had burned out, and they perceived that the
great heat had caused a part of the ashes to fuse with
the sand of the soil and thus produce the transparent
substance in question. It was thus that glass-mak-
ing was discovered."

**Was that long ago?" Jules inquired.

148

GLASS 149

^'This discovery, one of the most important ever
made, dates so far back that only a very vague record
of it has been preserved, and this record is probably
a mixture of fact and fable. But whether it be fact
or fable, the story teaches us at least one thing : sand
melted with ashes produces glass. Now, what can
the substance be that imparts to ashes the property
of thus transforming the sandf What is there in
ashes of such a potent nature as to bring about this
wonderful change ? ^ *

''There is soda,'^ Marie suggested, ''that same
soda that turns oil or tallow into soap.''

"It was in fact the soda from the marine plants
burned by the sailors that had brought about the
melting of the sand and the formation of lumps of
glass. Potash, which closely resembles soda in all
its properties, acts in the same way when it is heated
to a high temperature with sand. In both cases the
result of the fusion is glass, more or less colored,
finer or coarser, according to the purity of the ma-
terials used. The fine and perfectly colorless glass
of our goblets, decanters, and flasks is obtained from
potash and very white sand ; window-glass, which is
very slightly green, at least on the edge, is made of
soda and pure sand ; common bottle-glass, dark green
in color, or nearly black, is made of very impure sand
and ordinary ashes.

' ' The manufacture of window-glass is a very curi-
ous operation. In a furnace heated to a very high
temperature are large earthen pots or crucibles filled
with a mixture of soda and sand. When these two
substances are thoroughly melted together the result

150 THE SECRET OF EVERYDAY THINGS

is a mass of glass, red-hot and running like water.
Each crucible is removed by a workman and his as-
sistant, standing on a platform in front of an open-
ing through which the crucible is withdrawn. This
workman is called the blower. ' '

''Why blower f' asked Jules. ''Does he blowT'

"Indeed he does, and vigorously, as you will see.
His tool is an iron rod or tube with one end cased
in wood to enable him to handle the metal implement
without burning himself. The assistant heats the
other end by passing it through the opening in the
furnace, and then plunges it into the crucible. In
this way he gathers up a certain amount of paste-
like glass, which he molds into globular form by
turning it around -again and again on a block of wet
wood. That done, he again heats the glass at the
furnace opening, softens it, and passes the rod to
the workman, the glass-blower.

"The latter first blows gently into the tube, and
the mass of glass becomes inflated into a bubble
exactly as soap-suds would do at the end of a straw. ^ '

"I can make beautiful soap-bubbles by blowing
with a straw,'' said Emile. "Does the workman do
it like that r'

"Yes, just like that. He blows through his tube
into the mass of glass which, flexible and soft as long
as it remains red-hot, swells into a bladder. Then
the tube is raised aloft and the workman blows the
glass above his head. The bladder becomes flattened
a little by its own weight, at the same time gaining
in width. The blower lowers the tube again and
swings it to and fro like the pendulum of a clock,

GLASS 151

every now and then resuming his blowing with
greater force. By the action of its o^Yn weight,
which lengthens it, and the blowing, which distends
it, the mass of glass finally assumes the shape of a
cylinder.

^ ^ The completed cylinder ends in a round cap which
must be got rid of. To accomplish this the end of
the cylinder is held near the opening of the furnace
to soften it, after which the top of the cap is punc-
tured with a pointed iron. By swinging the tube
this puncture becomes enlarged and the cap dis-
appears. The cylinder, hardened now although still
very hot, is next placed on a wooden frame contain-
ing a number of grooves or gTitters for receiving the
cylinders. With a cold iron the workman touches
the glass where it adheres to the tube, and by this
simple contact a break occurs along the line thus
suddenly chilled, leaving the cylinder entirely freed
from the tube.

^ ' Notice, children, the clever device adopted by the
workman for detaching the glass from the tube with-
out shattering it. He merely touches the very hot
glass with a cold iron, and that suffices to produce a
clean break all along the line touched. Glass pos-
sesses this curious property of not being able to
withstand a sudden change in temperature without
breaking. Chilled suddenly, it breaks; heated sud-
denly, again it breaks. That is a warning to you
when you wash drinking-glasses or other glass ob-
jects. Beware of hot water if these objects are cold,
and of cold water if they are hot ; otherwise you run
the risk of breaking them instantly. When the cold

152 THE SECRET OF EVERYDAY THINGS

or the heat acts only along a predetermined line, it is
on that line, suddenly chilled or heated, that the rup-
ture occurs. That is how, without the slightest diffi-
culty, the workman separates the glass cylinder from
the iron tube to which it adheres.

^^This done, the next thing is to remove the cap
that still terminates one end of the cylinder. To
do this the workman encircles this cap with a band
of very hot glass, and then touches with a cold iron
the line thus reheated. Instantly a circular rupture
detaches the cap. Thus there is left on the frame a
glass muff open at both ends. To split this muff the
workman draws lengthwise, from one end to the
other, a red-hot iron point, and then touches the hot
line with a wet finger. A cracking follows, and the
muff splits open. It is next taken to a furnace
where, after being softened sufficiently, it is laid open
and flattened out with an iron rule on a cast-iron
plate. The final result is a large sheet of glass which
the glazier will cut later with a diamond point into
panes of any desired size.''

^^That is a very curious operation you have just
told us about, Uncle Paul,'' said Claire. ^^For my
part, I should never have suspected that a pane of
glass, so perfectly flat as it is, was first a glass ball
blown out like a soap-bubble."

^*And how are bottles made!" asked Jules.

^^For bottles glass is both blown and molded.
The tube, laden by the assistant with the proper
amount of melted glass, is passed to the blower, who
gives to the vitreous mass the shape of an egg ending
in a neck. The piece is then resoftened in the fur-

GLASS 153

nace and put into an iron mold. By energetic blow-
ing the workman inflates the glass and makes it
exactly fill the mold. This operation leaves the bot-
tom of the bottle still flat, but by pressure with the
point of a sheet-iron blade this bottom is driven up
inside and shaped like a cone. A band of melted
glass applied to the narrowed opening of the piece
gives the neck of the bottle. The seal that some
bottles bear, for example where the word liter is in-
scribed, is made by attaching a small disk of glass
while it is still soft, and stamping it with a mold
made of iron suitably engraved.''

Translator's Note. — Since the foregoing was written, machinery has
largely displaced hand-work in glass-making.

CHAPTEE XXVIII

IKON

OF all substances iron displays the greatest
power of resistance; and it is this property
that makes it the most useful of all our metals. All
sorts of tools are made of it, and without it our in-
dustries would come to an immediate standstill.''

*^ Yes, I see that iron is very useful,'' said Jules.

^'But perhaps you do not see how useful it is.
Reflect a moment and you will perceive that iron has
had something to do with nearly everything in the
house you live in. And at the very outset, in order
that the house may be built, there is need of stone
from the quarries, where picks and crowbars and
chisels and hammers are in constant use, all these
being, as you know, made of iron or steel. The
beams and joists of the framework come from trees
felled by the woodman's axe; and these timbers are
squared and shaped, fitted and adjusted with the help
of various carpenter's tools, all made of the metal
we are considering. Hardly a single one of our
articles of furniture would be practically possible
without this metal: we need the saw for cutting the
log into boards, the plane and the draw-knife for
smoothing the surface, the auger and the bit for bor-
ing the holes that are to receive the wooden pegs
which hold the parts together.

154

IRON 155

* ^ Our daily sustenance entails the use of iron in an
almost equal degree : it calls for the spade, the hoe,
and the rake for working the garden which gives us
our vegetables, and the plowshare for the heavy work
of the field which furnishes us with bread.

*^In the clothes we wear, too, we are" hardly less
dependent upon this indispensable substance. Of it
are made the shears that clip the wool from the
sheep's back, and of it also are made the carding-
and spinning- and weaving-machines that convert
the wool into cloth. Our most delicate fabrics, our
ribbons and laces, require the aid of this metal in
their manufacture ; and, finally, is not the needle used
in every stitch that is sewed, the needle so fine and
sharp-pointed that nothing else could take its place?''

^^It is plain enough," said Marie, ^^that iron is of
the utmost importance to us, though we usually give
it very little thought. It is so common that we make
no account of it, in spite of the immense service it
renders us."

''I should like to know how iron is obtained,"
Claire here interposed, ''if Uncle Paul will tell us."

''Iron ore," he explained, "is a yellow or reddish
stone of very unpromising appearance, with no re-
semblance to the metal so familiar to us. The fur-
nace in which it is worked is a sort of high tower,
swollen toward the base, tapering at the two ends,
and measuring at least ten meters, sometimes twenty,
in height. Through the upper door or mouth of the
furnace is poured coal by the cart-load, with frag-
ments of ore, and when once lighted the furnace
burns uninterruptedly, day and night, until the

156 THE SECRET OF EVERYDAY THINGS

masonry succumbs to the intensity of the heat.
Workmen are continually piling on fuel and ore as
fast as there is any subsidence in the burning mass,
while other workmen at the base of the furnace watch
the melting of the ore. Enormous blowing-machines
inject a continuous stream of air into the lower part
of the furnace by a great tube, through which this
current passes, not as a gentle breeze, but as a veri-
table tornado, raging and howling with an uproar
that is fairly deafening. If one takes a peep into the
furnace from the opening by which the tube enters,
a sort of white-hot inferno dazzles the eye. Here
stones melt like butter, and iron, separating from the
impurities mingled with it, falls in glowing drops
into a reservoir or trough at the base of the furnace.
When the trough is full a passage is opened by the
removal of the clay stopper that closed it, and the
liquid metal runs in a fiery stream into channels pre-
pared for it in the ground.

^^The metal thus obtained is impure iron and is
known as cast-iron. It is run into molds to make
stoves, grates, pots, and kettles, chimney-plates,
water-pipes, and countless other objects. Although
of great hardness, cast-iron is brittle : it breaks easily
when sharply struck.''

*^One day," said Emile, ^^a stove-cover broke into
three pieces just from falling on the floor.''

^^It is well to bear in mind," his uncle observed,
**that all our cast-iron implements are more or less
fragile, and that it takes but a blow or a fall to break
them. ' '

IRON 157

' * Then, ' ' remarked Claire, ^ * cast-iron won 't do for
making anything that must resist violent shocks —
hammers, for instance. ' '

^^No, cast-iron is worthless for tools that are sub-
ject to rough handling; pure iron alone has the neces-
sary resisting power. To purify cast-iron and con-
vert it into wrought-iron, the workers heat it in still
another furnace; and when it has become quite red
and soft it is hammered with a block weighing some
thousands of kilograms, and which is raised by ma-
chinery and then falls with all its weight. At each
blow from this enormous hammer what is not iron
escapes from the rest and runs off in a sweat of fire.

*' After this hammering the mass is grasped be-
tween two cylinders, one above the other, turning in
opposite directions. Dragged along by this power-
ful wringing-machine and flattened out by the irre-
sistible pressure, it becomes in a very short time a
uniform bar of iron. Shears next take hold of the
bar and cut it up into pieces of equal length. ' '

**Wliat! Are there shears that can cut iron
barsf exclaimed Claire.

^* Yes, my child ; in those wonderful factories where
human invention is brought to bear on the working
of iron there are shears that without the least ap-
pearance of effort cut clean through a bar of iron
with each snip, no matter if the bar be as big around
as a man's leg. With our scissors we could not more
easily cut a straw. ' '

^ ^ But such shears cannot be operated by hand ? ' '

**Nor are the two blades moved at the same time.

158 THE SECRET OF EVERYDAY THINGS

While one of them remains at rest on a support, the
other goes up and down as calmly and noiselessly as
you please, cutting with each downward stroke the
bar of iron offered it by a workman. ' '

CHAPTER XXIX

BUST

THE dull red that dims the luster of polished iron
or steel is, as you know, rust, or, in learned
language, oxide of iron; that is, iron mixed with
oxygen. As it comes from the mine, iron takes this
form of rust mingled with stone. What an unpre-
possessing appearance it then wears, this most use-
ful of all the metals ! It is an earthy crust, a reddish
lump, a shapeless mass, in which the presence of any
kind of metal whatever can be divined only after
painstaking research. And then it is by no means
enough to determine that this rusty matter contains
a metal; it is still necessary to find some means of
decomposing the ore and extracting the iron in its
true metallic state. What labor and experiment has
it not required to attain this end, one of the most
difficult imaginable ! How many fruitless attempts,
how many laborious trials !

^^ Other metals, the greater number of them, like-
wise rust, the color of the rust varying with the
metal. Iron turns a yellowish red; copper, green;
lead and zinc, white. Take a knife and cut through
a piece of lead. The cross-section shows a fine metal-
lic luster, but before long it becomes tarnished and
a sort of cloudy appearance is noticeable. This
change begins as soon as there is contact with the

159

160 THE SECRET OF EVERYDAY THINGS

air, and in course of time it extends, slowly indeed,
but surely, until it penetrates to the very heart of the
mass and ends by converting the lead into an earthy
substance quite different in quality. And the
greater number of metals undergo a similar deterior-
ation under like conditions. ' '

*^Then that green stuff we see on old copper coins
is rust?" asked Marie. ^^And the whitish coating
on the water-pipe of the pumpf

**Yes, it is rust in each instance. But all metals
are not equally subject to rust. Iron is one of those
that rust most quickly; next come zinc and lead; in
the third class are tin and copper ; and in the fourth
is silver, which remains free from rust with very
little care; finally, gold is still more immune and
never rusts.

*^Gold coins and jewelry of the remotest antiquity
come down to us as pure and brilliant as if made
yesterday, despite a sojourn of long ages in a damp
soil where other metals would have turned to shape-
less rust. Since it has such power of resistance to
destructive agencies, gold ought to be found, and in
fact is found, always retaining its metallic proper-
ties, especially its luster. In the bosom of the rocks
where it is disseminated — in its ore, as we say — it
forms scales, veins, and sometimes big nuggets,
which shine like jewels just from the goldsmith's
hands. Our ear-rings and finger-rings, carefully
kept in their casket, are not more brilliant than the
particles of this precious metal found in the heart of
a rock. Just as it occurs in its natural state it can
be put to immediate use ; all that is needed is to ham-

RUST 161

mer it and shape it. Hence it is the first of metals
to be discovered and used by man ; yet owing to its
extreme rarity it has never, in our part of the world,
been used for common tools, but has ever remained
the preeminently precious metal, reserved for
jewelry and coinage/'

CHAPTER XXX

TIN-PLATING

** TRON,'' said Uncle Paul, ''is abundant and cheap;
A furthermore, the hottest fire in our stoves and
grates cannot melt it, and it is able to withstand
rather rough usage. These qualities are highly im-
portant in cooking-utensils, which must resist the ac-
tion of fire without risk of melting, and have every
day to undergo bangs and falls. But unfortunately
this metal rusts on the slightest provocation ; contact
with a few drops of water for any length of time
suffices to cover it with ugly red spots which eat into
it and finally pierce quite through. This rapid de-
terioration is prevented by tinning.

''A metal is tinned by being overlaid with a thin
coating of tin, which resists rust. Now bear in mind
this important point, which I have already briefly
touched upon : rust develops only where air is pres-
ent. Also, it is promoted by various substances,
such as water, vinegar, and the juice of our vege-
tables and fruits. Nearly all the dishes we prepare
for the table tend by their mere contact to rust metals
capable of rusting, and especially iron. To prevent
the formation of rust, therefore, what must we do?
The answer is plain : keep our food and the air from
coming in contact with any metal that will rust. If
this contact never occurs, rust will never form, for
there will be nothing to cause rust.

162

TIN-PLATING 163

**Our obvious course, accordingly, is to coat the
corruptible metal with one that will protect it, and
this last must fulfil two conditions : it must not be
liable to rust; or, at any rate, it must be a metal
that rusts with difficulty, since otherwise one ill would
only be exchanged for another; and it must also be
a metal from which food will contract no injurious
properties. This double requirement is met by very
few metals. There are, first, gold and silver, both
too expensive for common us'e; and finally there is
tin. This metal is very slow to rust, and, further-
more, tin-rust, if it ever begins to form, does not form
in any quantity and has, besides, no harmful proper-
ties. Tin, therefore, furnishes us the metallic coat-
ing we need for preserving our iron utensils from
rust. ' '

** Would n't it be much simpler,'' asked Claire, *Ho
make these utensils wholly of tin in the first place and
so get rid of iron altogether?"

*^ There is one serious objection to such a course:
tin melts easily. A saucepan of this metal would
not hold out for five minutes against the heat of a
handful of glowing charcoal. What would become
of your stew in^ a cooking-utensil capable of melting
like wax over the fire!"

*^I see now that tin by itself would never do."

*'Nor would it answer for another reason : it offers
too little resistance, it bends under slight pressure,
it is knocked out of shape with a blow. We must
have two metals combined: iron to resist heat and
stand rough usage, and tin to prevent rust. If, how-
ever, the utensil is not to go over the fire, it can in

164 THE SECRET OF EVERYDAY THINGS

case of need be made of tin alone. Not very long
ago, in the country, tableware for company use was
of tin. Plates, platters, and soup tureens shone like
silver on the shelves of the dresser, and were the
pride of the housewife. Our measures for wine, oil,
and vinegar are of tin. The use of this metal in
preference to any other for utensils that are to come
in contact with our food is due to its perfect harm-
lessness. Tin keeps its cleanness and polish and —
a still more valuable property — communicates noth-
ing injurious to the substances it touches.

^^You are familiar with those wandering tinkers
with sooty faces who, a kettle over the shoulder and a
few old forks in one hand, go through the street,
crying their trade in a shrill voice. In the open
air, over a little charcoal fire, they restore rusty
covers to their first brilliance, mend kettles and
saucepans, and plate with tin utensils of iron and
copper, to keep them from rusting. The operation
is very simple: the piece to be tinned is first well
scoured with fine sand, and then heated over the fire,
and while it is still warm a little melted tin is rubbed
over the surface with a wad of tow. The tin takes
fast hold of the underlying metal and covers it with a
thin layer which will not come off with rubbing.
That is what is known as tin-plating.''

' ^ Then what we commonly called tin, ' ' said Marie,
*'is really iron covered over with tin?''

^^Yes, it is tin-plated iron, and is made by plung-
ing thin sheets of iron into melted tin. These tinned
sheets, light and strong at the same time, polished
and rust-proof, serve for the manufacture of num-

TIN-PLATING 165

berless utensils. The outfit of our kitchens consists
in great part of tinware. ' '

**But it consists also of copper- ware/ ' remarked
Jules.

**Yes; but copper has very dangerous properties
which call for the utmost caution on our part. Iron-
rust is harmless, I might even say healthful, in
limited quantities. Little children deficient in bodily
vigor are sometimes made to drink water impreg-
nated with a small quantity of rust from a few old
nails in the bottom of the water-bottle. Nothing,
then, is to be feared, so far as our health is concerned,
from the rusting of iron ; it is coated with tin, not as
a safeguard against danger, but to give the metal
cleanliness and greater durability.

^^Copper-rust, on the contrary, is a violent poison.
This rust, or verdigris, is all the more dangerous in
that it develops with extreme ease when copper
comes in contact with our articles of food, especially
when the latter contain vinegar or fat. Have you
ever noticed the greenish tinge imparted to the oil
in lamps and to the candle-drippings on candlesticks?
Well, this tinge comes from the copper that enters
into the metal part of lamps and candlesticks, and
is due to the verdigris dissolved in the oily matter.
Our food, containing as it almost always does some
slight proportion of fat or oil, contracts the same
greenish tinge by remaining any length of time in
contact with copper. Vinegar acquires it in a few
moments. This green substance from copper, al-
ways bear in mind, is a terrible poison which cannot
be too carefully shunned. The only safe course lies

166 THE SECRET OF EVERYDAY THINGS

in constant watchfulness and in a scrupulous cleanli-
ness that keeps all copper utensils always bright and
free from the slightest indication of a green speck.
For greater safety it is even preferable to use only
tinned ware for culinary purposes. Proof against
rust under its coating of tin, copper then ceases to be
injurious, but only on condition that the tin coating
is maintained intact, never uncovering a particle of
the poisonous metal. As soon as the tin becomes dim
and shows a little of the red underneath, the utensil
should be retinned.

^^Lead is no less dangerous than copper, but this
metal enters very little into domestic use, unless it be
for cleaning bottles. A handful of small shot shaken
up in water serves excellently to remove by fric-
tion the impurities clouding the inside of the glass.
This practice, however, is not free from one grave
danger. Suppose a few particles of lead are re-
tained in the bottom of the bottle and left there un-
observed. Wine, vinegar, or whatever other liquid
is afterward poured in, is likely to cause the lead to
rust, and will thus contract properties highly injuri-
ous to health. Without any one 's suspecting it there
will lurk in the bottom of the bottle that is daily used
a permanent source of poison. You see therefore
what care should be exercised in order that not a
particle of lead may be left behind after this metal
has been used for cleaning purposes. Never forget
that copper and lead are two poisonous metals, and
that any carelessness in their domestic use may suf-
fice to imperil our very lives.''

CHAPTER XXXI

POTTERY

«*fTlRAVELLERS tell us of the strange methods
M. adopted in preparing food by certain savage
tribes among whom that precious culinar}^ utensil,
the earthen pot, is unknown. They tell us, for ex-
ample, that the Eskimos of Greenland boil their meat
in a little skin bag, as I have already ^ related to you.
The bag is not placed over the fire, but is filled with
water and the food to be cooked, after which stones
heated red-hot are dropped into it ; and thus, labori-
ously and imperfectly, by repeated heating of the
stones and dropping them into the bag, a dish of half-
cooked meat mixed with ashes and soot is at last
prepared.

^'To such extremities we might be reduced if it
were not for those little earthen pots, sold at a penny
apiece, that rescue us from the dire straits familiar
to the Eskimo. , Let us now consider how this simple
kitchen utensil is made.

^^From the modest little porringer to the sumptu-
ous porcelains adorned with rich paintings, every
piece of pottery is made of potters' earth, or clay,
which is found almost everywhere, but by no means
of uniform quality. There are yellow clays, red
clays, ash-colored clays, dark clays, and perfectly

1 See "Our Humble Helpers."

167

168 THE SECRET OF EVERYDAY THINGS

white clays. These last are free from all foreign
matter; the others contain divers alien substances.
All are easily kneaded with water, forming a sort of
unctuous dough capable of taking any prescribed
form. The coarsest clays serve for making bricks,
drain-pipes, flower-pots, and so on; clays that lack
purity but are still of fine texture are used for com-

Potter's Wheel

a, partly molded clay: h, guiding measure; c, revolving wheel, screwed on
shaft d, Avhich is propelled by horizontally moving treadle-apparatus /, and
steadied by fly-wheel h, pivoted on block g; e, box for holding balls of clay,
water-vessel, sponge, tools, etc.

mon pottery ; and, finally, clays of extreme purity, of
snowy whiteness, furnish us porcelain. This degree
of purity is very rare in clay, being found in. France
only in Haute- Vienne, around Limoges. Clay of in-
ferior quality occurs in abundance in nearly all parts
of the world.

*^In order to give to moistened clay quickly and
easily a regular' form the potter makes use of the
potter's wheel. As illustrated im the picture I here

POTTERY 169

show you, under the potter's work-table is a horizon-
tal wooden wheel which the operator sets in motion
with his foot. The axle of this w^heel carries at its
upper end a small disk, in the center of which is
placed the lump of clay that is to be shaped by the
potter. The latter thrusts his thumb into the form-
less mass, which rotates with its supporting disk,
and this action suffices to produce a symmetrical
cavity because of the regularity of the motion im.-
parted to the clay. As fast as the thumb enlarges
the cavity the other fingers are applied to the outside
to hold the mass in place, to give it the desired shape,
and to preserve a uniform thickness of wall through-
out. In a few moments the piece is fashioned, and
we see the lump of clay hollowed out and made to
stand up in the form of a bowl or jar having just
the outline and thickness desired by the artisan.
The application of the palm of the hand, slightly
moistened, suffices to polish the surface. Finally,
with tools designed for the purpose the piece is orna-
mented with moldings. For example, it is enough to
touch the rotating object with an iron point to trace
an engraved line around it.

^^When the potter's wheel has done its part the
vessel, still damp, is left in the air to dry, after which
it is dipped into a bath of water and fine dust of
lead ore. By the action of fire this dust will pres-
entely be incorporated with the surface clay on which
it rests and will become a sort of glaze or varnish,
without which the vessel would be permeable by
liquids and would allow its contents gradually to
ooze out and escape. To complete the whole the ves-

170 THE SECRET OF EVERYDAY THINGS

sel is subjected to a high temperature in an oven,
where the clay bakes and becomes hard stone, while
the lead dust covering it melts and combines with
the substance of the clay, spreading over the surface
as a brilliant varnish having the color of honey. In
this wise the more ordinary pottery is made, the pot-
tery constantly used in our kitchens and so valuable
for its ability to bear heat without breaking.

^^In most cases the coating of lead has nothing to
be said against it, for our articles of food do not, as
a rule, produce any effect upon it. Vinegar alone is
of a nature to dissolve it slowly when kept long in
contact with it, especially if the vessel in question
has not been properly baked. Hence it would be
highly imprudent to use pots or jars having this lead
glaze on the inside for keeping gherkins, capers, and
other pickles preserved in vinegar. This latter
might in course of time dissolve the metal contained
in the glaze and thus contract poisonous properties,
so that in seasoning a dish with a handful of capers
one might ru»n the very serious risk of lead-poisoning.
Pickles of that sort should be kept in glass jars or
in common earthenware not glazed on the inside.

*^ Crockery is made of clay of fine quality. Its
glaze, which is of a beautiful milky whiteness, is pre-
pared from tin, a harmless metal. Thus our food,
even when containing vinegar, never contracts in-
jurious properties from contact with this glaze.

^^I will say as much for the glaze of porcelain,
which contains no metal in its composition, but re-
sults from the melting of the surface clay itself in
the heat of the oven, the clay being of extreme purity

POTTERY 171

and whiteness. Hence we here have no fear of any
lead varnish, which is recognizable from its honey-
yellow hue and is employed only for common pottery.
But, as I said before, this latter kind of glaze is to
be feared only in case of prolonged contact with
vinegar. ' '

CHAPTER XXXII

COFFEE

HE plant that produces coffee is called the
coffee-tree. This is in reality little more than
a shrub, bearing some resemblance to a small pear-
tree in its rounded top and bushy branches. Its
leaves are oval and shiny ; its blossoms, which resem-
ble those of the jasmine and have a sweet smell, are
grouped in small bunches in the axils of the leaves.
These blossoms are succeeded by berries, first red
and then black, having the appearance of our cher-
ries, but with very short stems and crowded close

together. Their
pulp is insipid and
sweetish, enclosing
two hard seeds,
round on one side,
flat on the other,
and united by their
flat sides. These
seeds are the so-
called coffee-beans
which we use after
roasting them in a sheet-iron cylinder revolving over
the fire. In color they are half-way between white
and green, but turn to a chestnut hue in roasting.
**The coffee-tree can thrive only in very warm

countries. It is indigenous to Abyssinia, where it

172

Fruiting Branch of Coffee Plant

a, flower ; 6, section of berry, showing en-
closed nutlets.

COFFEE 173

grows abundantly, especially in the province of
Kaffa, from which it seems to have taken its name."
In the fifteenth century the coffee-tree was intro-
duced from Abyssinia into Arabia, and it is there
that the plant has found a climate most favorable for
the development of its peculiar properties. Indeed,
the most highly prized coffee comes to us from the
southern provinces of Arabia, especially from the
neighborhood of Mocha. '^

*'Then,'^ said Marie, ^^when we speak of a coffee
of superior quality as Mocha, we give it the name of
the town that furnishes the best.''

** Precisely. Look at the map and you will find
Mocha very near the southern end of Arabia, at the
entrance to the Red Sea. It is in this comer of the
earth, under a burning sun, that the most highly
esteemed coffee ripens.

*'The Dutch were the first Europeans to turn their
attention to coffee ; they introduced it into their East
Indian colonies, notably Batavia, whence a few young
trees were sent to Amsterdam to be cultivated in hot-
houses, as the climate of Holland would by no means
ensure the thriving of this warmth-loving shrub in
the open air. '

' ' One of these young trees was given to the Botani-
cal Garden of Paris, where care was taken to multi-
ply it under glass, and one of the plants thus obtained
was given to Declieux, who started for one of our
colonies, Martinique, with his little coffee-tree rooted
in a pot. Never, perhaps, has the prosperity of a
country had so humble a beginning : this feeble coffee-
plant, which a sunbeam might have dried up on the

174 THE SECRET OF EVERYDAY THINGS

way, was to be for Martinique and the other Antilles
the source of incalculable riches.

^* During the journey, which was prolonged and
made difficult by contrary winds, fresh water ran
short and the crew was put on the most meager ra-
tions. Declieux, like the others, had only one glass
of water a day, just enough to keep him from dying
of thirst. The young coffee-tree, however, needed
frequent watering in that extremely hot climate.
But how water it when thirst devours you and every
drop of water is counted? Declieux did not hesi-
tate to devote his own scanty allowance to the needs
of his charge, one day giving it the whole glass, and
the next going shares with it, preferring to sutf er the
most painful of privations in order to reach h^ des-
tination with the young coffee-tree in good condi-
tion. And this satisfaction was not denied him. To-
day Martinique, Guadeloupe, Santo Domingo, and
most of the other Antilles are covered with rich coffee
plantations, all owing their origin to the feeble plant
imported by Declieux.^'

^^That plucky traveler is a man to be admired,''
declared Jules, ^ ' and every time I drink coffee I shall
think of him and what he did. ' '

** Nothing in our part of the world can compare
in beauty with an orchard of coffee-trees bearing
simultaneously as they do, throughout most of the
year, leaves of a lustrous green, white blossoms, and
red berries, vegetation in those sun-favored regions
knowing scarcely a moment's repose. Over the per-
fumed tops of the trees hover butterflies whose wings,
as large as both hands, astonish one with the magnifi-

COFFEE 175

cence of their coloring. In the forks of the topmost
branches the humming-bird, a living jewel, builds its
nest of cotton, half the size of an apricot. On the
bark of old tree-trunks great beetles shine with more
radiant splendor than the precious metals. In an at-
mosphere laden with sweet odors negroes carrying
baskets on their arms go through the plantations
from one cotfee-tree to another, carefully gathering
the ripe berries one by one so as not to disturb those
that are still green. Scarcely is this harvest gath-
ered when other berries redden, and then still others,
while fresh buds form and new blossoms open.

^^The coffee-berries, or cherries, as they are called,
are passed through a kind of mill which crushes and
removes the pulp without touching the seeds. Then
these are exposed to the sun. Every evening, to pro-
tect them from the dew, they are piled in a heap and
covered with large leaves, to be spread out again
the next morning. When the drying process is fin-
ished they are winnowed, the spoiled seeds rejected,
and the harvest is ready for export. ''

''After that," said Claire, ''the coffee only has to
be roasted and ground and it is ready for use. Does
any one know who was the first to use it?"

"According to a tradition current in the East, the
use of coffee goes back to a certain pious dervish who,
wisliing to prolong his meditations through the night,
invoked Mohammed and prayed to be delivered from
the need of sleep."

"A pious dervish, did you say?" Emile interposed.
"I don't know what a dervish is."

"It is the name given in Oriental religions to cer-

176 THE SECRET OF EVERYDAY THINGS

tain men who renounce the world and devote them-
selves to prayer and contemplation.'^

'^And Mohammed?''

*^ Mohammed is a celebrated character who about
twelve centuries ago founded in Arabia a religion
that has now spread over a great part of the world,
especially in Asia and Africa. This religion is called
Mohammedanism or Islamism, and Mohammed is
often designated by the title of Prophet.

' ^ To return to the dervish who wished not to sleep
that he might have so much the more time for prayer
and meditation, he addressed his petition to Mo-
hammed, and the Prophet appeared to him in a
dream, advising him to go in quest of a certain shep-
herd. This man told the dervish that his goats re-
mained awake all night, leaping and capering like
fools, after having browsed on the berries of a shrub
that he pointed out to him. It was a coffee-tree,
covered with its red fruit. The dervish hastened to
try on himself the singular virtue of these berries.
That very evening he drank a strong infusion of
them, and, lo and behold! sleep did not once come
to interrupt his pious exercises all night long.

*^ Rejoiced at procuring wakefulness whenever he
desired it, he shared his discovery with other der-
vishes, who in their turn became addicted to the
sleep-banishing drink. The example of these holy
persons was followed by doctors of law. But before
long it was discovered that there were stimulating
properties in this infusion used for dispelling sleep,
whereupon it began to find favor with those who had
no desire to be kept awake, until finally the bean

COFFEE 177

chanced upon by the goats came into general use
throughout the East.

^^I advise you not to yield a blind belief to
this popular tradition, for in reality it is not known
by whom or in what circumstances the properties
of coffee were first discovered. One point only re-
mains incontestable, and the story of the dervish
brings it out well : it is the property coffee possesses
of keeping the mind active and driving away sleep.''

^^ Coffee, then, really prevents one's sleeping?"
asked Marie.

^*Yes, but not every one feels this singular influ-
ence in the same degree. There are some not af-
fected by it at all, and others, of a delicate and nerv-
ous temperament, who cannot close their eyes all
night long if they happen to take coffee in the eve-
ning. ' '

^^And how about taking it in the daytime!"

**In that case the same objection does not present
itself ; there is even an advantage in having the mind
fully active, especially if one is engaged in mental
work. But for the most part coffee is a simple stimu-
lant that favors digestion and excites new vigor.
Long habit makes it for many a drink of prime
necessity.

*' Prepared from the green berry just as it comes
from the country that produces it, the infusion of
coffee is a greenish liquid, odorless and tart, which
acts powerfully on the nerves."

**Is that the way," asked Claire, ^Hhat the dervish,
taught by the capering of the goats, took his first cup
of coffee?"

178 THE SECRET OF EVERYDAY THINGS

* ^ Probably. Nothing but the ardent desire to com-
bat sleep could have induced him to continue the
dose, for the drink prepared in this way is very far
from being palatable. The qualities that make us
desire coffee, especially its fragrant aroma, are de-
veloped only by roasting ; hence this operation should
be performed with a certain degree of care. If in-
sufficiently roasted, the coffee-beans remain green in-
side ; then they are hard to grind in the mill and give
a greenish yellow infusion with no aroma. Roasted
too much, they are reduced to charcoal on the out-
side; then the infusion is very dark, bitter-tasting,
and without aroma. Coffee is roasted to a nicety
when it gives out an agreeable odor and has taken
on a dark chestnut color.

^^ Coffee should be ground fine so as to yield its
soluble ingredients readily to the water ; and, finally,
the infusion should never be boiled, because then
the aromatic principle is dissipated, being carried
away by the steam. Coffee allowed to boil would
soon be nothing but a bitter liquid bereft of the quali-
ties that give it its value. The best temperature is
the one that approaches the boiling point but never
quite reaches it.

**The high price of coffee has given rise to many
attempts to substitute cheaper home-grown products
for the precious berry. It has become customary to
roast chicory roots, chick-peas, and acorns, to mix
with the ground coffee. The only resemblance to
coffee possessed by these various substances lies in
the burnt odor, the chestnut color, and the bitter
taste, with none of coffee's efficacious properties.

COFFEE 179

Allured by the hope of gain, the merchant may exalt
in high-sounding terms of praise the virtues of these
cheap substitutes, but you may be sure he never has
any of them served at his own table. ' '

*^They say,^' Marie remarked, ^'that coffee sold
already ground is sometimes mixed with one of those
worthless powders you speak of."

^ ^ That is only too true. This fraud can be avoided
by buying the coffee-beans either already roasted
or green, and in the latter case roasting them one-
self.''

CHAPTER XXXIII

SUGAR

COFFEE calls for sugar," resumed Uncle Paul
the next day. '^Who can tell me what sugar
is made of?"

All remained silent until Emile rather hesitatingly
ventured to say:

^*I have heard, Uncle, that it is made of dead
people's bones."

**And who told you that, you simple child?"

**0h, a friend of mine," replied Emile, in some
confusion at this strange notion, the falseness of
which he now began to suspect without being able to
explain it.

^^Your friend," said his uncle, ^^was making game
of your credulity when he told you any such ridicu-
lous story as that. Sugar has no lugubrious origin
of that sort, although there is a grain of truth in
what your friend said. To purify sugar and make it
as white as snow, use is made of animals' bones after
they have been burnt to charcoal, as I will explain to
you presently. But these bones, as soon as they
have played their part, are thrown away and not the
slightest trace of them is left in sugar as it comes
to us. It is probably this use of bones in the manu-
facture of sugar that has given rise to the singular
idea you repeat after your friend.

180

SUGAR 181

^'Then there isn't one of you that knows where
sugar comes from. But you do know at least many
kinds of fruit that have a very sugary taste, such as
melons, for example; grapes, figs, and pears."

'^Melons are so sweet," put in Claire, "one would
think they were preserved in sugar. Very ripe
pears, too, are just as sweet; and so are grapes and
figs."

**If these various kinds of fruit have the sweet,
sugary taste to such a high degree, it proves that
they contain sugar in their juice and m their pulp."

**And yet Ave don't sweeten them; we eat them just
as they are."

"We do not sweeten them ourselves, it is true, but
somebody does it for us; and that somebody is the
plant, the tree that bears them. With a few poor
materials which the roots derive from the soil, and
with the drainage from the dunghill, the plant, an
inimitable cook, concocts a certain amount of sugar
and stores it up in the fruit for our delectation.
Emile was inclined to believe, rather against his will,
that sugar was made from dead people's bones; but
here we have quite a different explanation of the
matter : I tell him that the toothsome dainty really
comes from certain filthy substances mixed with the
soil under the form of manure. Before becoming the
exquisite seasoning of the peach, fig, and melon, the
sugary matter was nothing but foul refuse. This
ignoble origin is not peculiar to sugar: everything
offered us by vegetation is derived from a similar
source — everything, even to the sumptuous coloring
and the sweet perfume of flowers. To effect this

182 THE SECRET OF EVERYDAY THINGS

marvelous transformation man's skill would be
powerless; the plant alone is capable of such a
miracle. Out of a few materials which the earth,
water, and air supply, it makes an infinite variety of
substances having every sort of flavor and smell —
in fact, all imaginable qualities. For that reason T
have called it the inimitable cook. Man, then, does
not really manufacture the sugar ; it is the plant, the
plant alone, that produces it, and man's work is
limited to gathering it where he finds it ready-made
and separating it from the various substances ac-
companying it.

^^I have already mentioned several kinds of fruit
as containing sugar, the melon in particular. Often
other parts of plants contain it too. Chew a stalk of
wheat when it is still green, or of reed-cane, or the
first blade of young grass. You will find they have
a slightly sugarj^ taste. There is not a blade of grass
in the meadow but has its stalk preserved in sugar.
In other plants it is the root that becomes the store-
house of saccharine matter. Couch-grass, the com-
monest weed in our fields, has a very sweet root.
The enormous root of the beet is sweeter still, being
a veritable candy shop, so much sugar does it con-
tain. You see how widely dispersed sugar is
throughout the vegetable kingdom, although few
plants lend themselves to the industrial extraction
of this precious substance, because they contain so
little of it. Two plants only, incomparably richer
than the rest, furnish nearly all the sugar consumed
the world over; and they are the sugar-cane and the
beet-root.

SUGAR

183

^^The sugar-cane is a large reed two or three
meters high, with smooth, shiny stalks having a
sweet, juicy marrow. The plant came originally
from India and is now cultivated in all the warm
countries of Africa and America. To get the sugar,
the stalks are cut when ripe, stripped of their leaves,
made into bundles, and then
crushed, in a kind of mill, be-
tween two cylinders turning
in opposite directions a short
distance apart. The juice
thus obtained is sometimes
called cane-honey, which
shows you how sweet it is.
It is put into large kettles
and boiled do^\^l to the con-
sistency of syrup. In the
course of the process a lit-
tle lime is added to clarify
the syrup and separate the impurities from it.
When the evaporation has proceeded far enough the
liquid, still boiling, is poured into cone-shaped
earthen molds ; that is to say, molds having the shape
of a sugar-loaf. These molds, turned point down-
ward, have at this end a small hole that is kept
stopped up with a straw plug. As soon as they are
full of syrup they are left to cool slowly. Little by
little the syrup crystallizes and becomes a compact
mass, after which the straw plug is removed and the
small amount of liquid that has not hardened escapes
through the hole at the point, drop by drop. This
first operation gives raw sugar, commonly called

Sngar-Cane

a, part of the inflorescence;
b, a Bpikelet.

184 THE SECRET OF EVERYDAY THINGS

brown or moist sugar. Its color is not yet pure
white, and there is something disagreeable about the
taste. To make it perfectly white and to free it
from certain ingredients that mar the perfect quality
of its flavor, it undergoes a purifying process in fac-
tories called refineries.

**In France sugar is obtained from the beet-root,
an enormous root with white flesh, cultivated in vast
fields for the manufacture of sugar in several of our
northern departments. ' '

^*The beets I usually see in the field,'' said Marie,
**have red flesh. Do they also contain sugar?"

**Yes, they contain some, but less than the white
beets. Besides, their red coloring would add to the
difficulty of obtaining perfectly white sugar. So the
white beets are preferred. The roots are carefully
washed and then reduced to pulp under large graters
worked by machinery. Finally this pulp is placed
in woolen sacks and subjected to pressure. The juice
thus extracted is treated like that of the cane and
yields a similar raw or brown sugar, which must be
refined in order to attain perfection.

*^The process of refining is based on a certain prop-
erty of charcoal which you must learn before going
farther.

'^Let us take from the fireplace some very light
coals, well calcined, and reduce them to coarse pow-
der. Next let us mix this black powder with a little
highly colored vinegar and strain the mixture
through a piece of very fine linen or, better still,
through filter-paper placed in a funnel. The linen,

SUGAR 185

and still more the paper, will retain the charcoal to
the smallest particle, the vinegar alone passing
through. But what a singular change will have
taken place ! The vinegar, at first of a dark reddish
hue, has become limpid, showing hardly a trace of
red ; as far as color is concerned it looks almost like
water. But it has lost none of its other properties ;
its pungent odor and strong taste are the same as at
the beginning. Only the color has disappeared.
This experiment teaches us something of great inter-
est : charcoal has the property of bleaching liquids by
taking to itself the coloring matter contained in them.

^'This property is carried to its highest develop-
ment in a charcoal made from the bones of animals
and called for that reason animal charcoal or bone-
black. Filtered through this substance in powdered
form, vinegar and red w^ine become as colorless as
water, without losing any of their other properties.
A few words will tell you how this curious charcoal
is made that takes the color out of liquids so easily.
Throw a bone on the fire : soon you will see it flame
up and turn quite black. If you waited too long,
what is now charcoal would be burnt up entirely and
the bone would in the end become quite white. But
withdrawn before being wholly burnt up, it is as
black as common charcoal. Reduce this charred bone
to powder, and you will have real bone-black.

^*Well, it is by means of half -burned bones, bone-
black in fact, that sugar is refined. Bones of all
kinds of animals, refuse from the slaughter-house,
kitchen remnants, carcasses found in sewers, all are

186 THE SECRET OF EVERYDAY THINGS

carefully gathered up and converted in kilns to bone-
black for the bleaching of sugar until it assumes the
whiteness of snow.''

*^That, then/' said Emile, *4s what started my
friend's jest. Sugar is not made of dead people's
bones, but bones turned into charcoal are used to
whiten it. ' '

^^Yes," his uncle agreed, ^^that undoubtedly ac-
counts for your friend's odd notion."

'^If it were not for their being burned in a hot fire
in the first place," Emile continued, ^^I should be dis-
gusted to think of bones picked up anywhere being
used in sugar-refineries. Fire purifies them; other-
wise I should stop eating sugar. ' '

'* Banish all repugnance on that score, my child.
These bones are so thoroughly calcined that not the
slightest trace of their former impurity remains.
Let me tell you how they are used. The brown sugar,
be it from cane or beet-root, is dissolved in hot water
and the syrup thus obtained mixed with the proper
quantity of bone-black, which draws to itself the im-
purities that give raw sugar its yellowish color and
unpleasant taste. This mixture is strained through
thick woolen cloths which act as filters. The char-
coal remains above with all the impurities it has con-
tracted, while the syrup passes through as limpid as
the water that gushes from a rock. The sugary
liquid is then boiled down and finally poured into
cone-shaped molds, where it hardens into sugar-
loaves of irreproachable whiteness and flavor."

CHAPTER XXXIV

TEA

AVE you ever examined carefully the grounds
in the bottom of a pot of tea ? A pinch of tiny
round bluish-black grains is put into hot water ; after
steeping these round grains are found to have turned
into easily recogniz-
able little leaves.''

**Yes, indeed,''
Marie made haste to
reply, *'I have seen
the grains of tea
swell in hot water, un-
fold, and finally
spread out into little
leaves. Tea must
come, then, from the
foliage of some sort
of plant."

*' You are right : tea is the leaf of a shrub of which
this picture will give you an idea. It is an ever-
green shrub, two meters or more in height, its foliage
tuftlike and shiny, its flowers white, and its seeds in
the form of small capsules in clusters of three. Its
cultivation is confined to China and Japan.^

1 Since 1876 tea has been grown in increasing quantities in Ceylon,
Natal, Brazil, and the West Indies; and some of our own southern
States have also tried, with varying success, to raise the plant. —
Translator.

187

Branch with Flowers of Tea

a, leaf, showing the nervation ; b, seed-vessel
in process of opening ; c, a seed.

188 THE SECRET OF EVERYDAY THINGS

**In China the tea plantations occupy sunny hill-
sides in the vicinity of watercourses. The leaves are
gathered, not by the handful, but one by one and
with the utmost care. Minute as such work appears,
it is done rapidly by trained hands, one person being
able to pick from five to six kilograms a day. The
first picking occurs toward the end of winter, when
the buds open and let the nascent leaves expand.
This harvest, considered the best of all, is called im-
perial tea, being reserved for the princes and rich
families of China. The second picking takes place
in the spring. At this time some of the leaves have
finished growing, while others have not yet reached
their full size; nevertheless they are all gathered
indiscriminately and then picked over and assorted
according to their age, dimensions, and quality. The
third and last picking is made toward the middle
of summer, when the leaves are of tuftlike appear-
ance and have attained their full growth. This is
the coarsest and least-esteemed kind of tea. When
the harvest is over, its completion is celebrated by
public festivals and rejoicings."

*^The harvesting of this leaf must then be a very
important event to the Chinese," observed Claire.

**Yes, because tea is the customary drink of the
Chinese, being to them what wine is to us; and tea
also furnishes them one of their most important
articles of commerce. Is n't that reason enough for
public rejoicing, especially in a country where every-
thing pertaining to agriculture is held in high honor?

^^ Before taking the form of tea as we know it, the
leaves have to undergo a certain preparation. This

TEA 189

work is done in public establishments where there are
little furnaces about a meter high, on each of which
is placed an iron plate. When the plate is hot
enough the operator spreads the newly gathered
leaves on it in a thin layer. While they are shrivel-
ing and crackling in contact with the burning iron,
they are stirred briskly with the naked hand until the
heat can no longer be endured. Then the operator
removes the leaves with a sort of fan-shaped shovel
and throws them on to a table covered with mats.
Around this table sit other workers who take the hot
leaves in small quantities and roll them between
their hands, always in the same direction. Still
others fan them continually after they are rolled, so
as to cool them as quickly as possible and thus pre-
serve the curled shape they have just received. This
manipulation is repeated two or three times in order
to drive out all moisture from the leaves and give
them a permanent curl. Each time the plate is
heated less and the drying is conducted more care-
fully and slowly.

**The use of tea spread to Europe toward the
middle of the seventeenth century. It is said that
about this time some Dutch adventurers, knowing
that the Chinese made their customary drink from
the leaves of a shrub grown in their country, took it
into their heads to carry them a European plant,
sage, to which great virtues were attributed in those
days. The Chinese accepted this new article of com-
merce and in exchange gave them some tea, which the
Dutch took back to Europe. But the use of the Euro-
pean herb was of short duration in China, whereas

190 THE SECRET OF EVERYDAY THINGS

tea was so highly appreciated in Europe that it soon
came into general use.

*^ There is a tradition in China much like the one
current in Arabia concerning coffee. According to
this tradition, a certain pious and noble personage,
Dharma by name, went from India to China thirteen
or fourteen centuries ago to spread the knowledge of
the true God in that country. In order to stimulate
the people by his own example he led a very austere
life, imposing the severest mortifications on himself
and consecrating his days and nights to prayer.
Worn out by fatigue after a few years, and finally
overcome by drowsiness, it sometimes happened that,
in spite of himself, he would fall asleep in the very
midst of his meditations. In order to keep himself
awake and continue his pious exercises without inter-
ruption, he had recourse to the frightful expedient of
cutting off his eyelids, which he threw on the ground.
Heaven was moved to pity by this heroic sacrifice :
the holy man's eyelids took root in the soil as if they
had been seeds, and there sprang from them during
the night a graceful shrub covered with leaves. That
was the first tea-plant. The next morning, passing
by the same place, the mutilated holy man glanced
down at the spot where he had thrown his eyelids.
He could not find them, but in their place he saw the
divine shrub to which they had given birth. A secret
inspiration prompted him to eat of the leaves of this
miraculous shrub, and he obeyed the impulse. To
his great satisfaction he soon found that this nourish-
ment strengthened him, drove sleep away, and kept
his mind active. He advised his disciples to eat of

TEA 191

the shrub also, and the fame of tea spread far and
wide, its general use in China dating from that
time.

^'I need not tell you that this tradition is really
only a fable emphasizing the dominant properties of
tea, just as the Arabian legend concerning the caper-
ing of goats and the wakefulness of the dervish is
based on those of coffee. A shrub sprung from the
eyelids which a holy man had cut off in order not to
succumb to sleep ought, above all, to prevent sleep.
Tea shares this singular property with coffee. An
infusion of its leaves acts on the nerves when it is
taken strong and in considerable doses. Taken in
moderation, it is an agreeable drink, stimulating the
stomach and aiding the process of digestion.

^^The various kinds of tea kno\^Ti to commerce are
classed, according to the size of their grains, as pearl
teas and gunpowder teas, the former having larger
grains than the latter. They are divided again ac-
cording to color into green teas and black teas.
Green teas have a bitter and pungent taste and a
strong odor, excite the nerves and prevent sleep.
Black teas do not have this property in so pro-
nounced a deg?:"ee, being less stimulating, weaker, and
not so strongly scented. The preparation of tea
calls for the same care as that of coffee: it should
not be boiled, as that would dissipate the odor and
take away the crowning excellence of the beverage.

''With us tea is hardly more than a medicine used
to alleviate certain stomach troubles; but in many
countries besides China it is a daily drink, appear-
ing on the table several times in the twenty-four

19^ THE SECRET OF EVERYDAY THINGS

hours. In England, the European country most ad-
dicted to this drink, the annual consumption amounts
to twenty-five million kilograms.'*

CHAPTER XXXV

({

CHOCOLATE

N the hottest countries of the two Americas,
notably in Mexico, the Antilles, and Guiana, there
is cultivated a tree of about the size of our cherry-
tree, called the cacao or chocolate tree. ' '

^^What a queer name that is — cacao!" Claire ex-
claimed ; ^ ^not a bit like any of our fruit-trees. ' '

^^This queer name has come do^vn to us from the
primitive inhabitants of
Mexico, a people who tat-
tooed their red skin with
horrible designs and wore
their hair standing up in a
menacing tuft adorned with
hawks' feathers. Their lan-
guage was composed of
harsh guttural sounds which
to our delica^te ears would
seem more like the croaking
of frogs than the speech of
human beings. You have a
sample in the name of the ^^^*^°^ ^^^°^^ «^ ^^^""
tree I have just mentioned. The Mexicans, when
the Spanish visited them for the first time under the
lead of Fernando Cortez, soon after the discovery
of America by Columbus, were devoting careful at-

193

194 THE SECRET OF EVERYDAY THINGS

tention to the cultivation of the cacao tree, from
which they obtained their chief article of food,
chocolate. ' ^

' ' The same chocolate that is used for making those
delicious tablets we all like so muchT' asked Jules.

^^The same, at least as far as the essential ingre-
dients are concerned. We owe the invention of
chocolate to the ancient savages of Mexico, ferocious
Indians who honored their idols by offering them
human victims whose throats they cut with the sharp
edge of a flint. The tree that furnishes the chief
constituent of our chocolate confectionery is the
cacao, the name of which sounds so harsh to your
ears.

^^This tree grows, as I said, to about the size of
our cherry-tree. Its leaves are large, smooth, and
bright green. Small pink flowers grouped in little
clusters along the branches are succeeded by fruit
having the shape and size of our cucumbers, with ten
raised longitudinal ribs as in melons. These cacao-
pods, as they are called, turn to a dark red when ripe.
Their contents are composed of soft white flesh,
pleasantly acid, in which are embedded from thirty
to forty seeds as large as olives and covered with a
tough skin. Freed from all these wrappings, the
seeds take the name of cacao-nibs and constitute the
essential ingredient of chocolate.

*^Much as in the case of coffee, cacao (also called
cocoa) is first roasted, a process that turns the white
kernels to a dark brown. That is the origin of the
brown color of chocolate. After roasting, the hard

CHOCOLATE 195

skin that covers the kernels is broken up and thrown
away; then the kernels themselves, first thoroughly
cleaned, are crushed on a very hard polished stone
with the aid of another stone or an iron roller.
These kernels are rich in fat somewhat resembling
our ordinary butter, and hence called cacao-butter. ' '

* * There is butter in those seeds, real butter such as
we get from milk! '^ asked Claire.

**Yes, my dear, real butter, or something very
similar. Of what do the cow and the sheep make the
butter that we get from their milk! Evidently of
the grass that they eat. What wonder is it, then,
that vegetation should be able to produce butter if it
can supply animals with the materials for butter?
I hope to come back to this subject some day, and you
will see that in reality plants prepare the food that
animals give us.

^^But let us return to cacao-butter. To keep this
fatty substance fluid and thus facilitate the working
of the paste, it is customary to place live coals under
the stone on which the seeds are being crushed.
With a little heat the vegetable butter melts and
forms, with the solid matter of the seeds, a soft
brown paste that can be easily kneaded. With this,
paste is mixed, as carefully as possible, an equal
weight of sugar, then some flavoring extract, usually
vanilla, to give aroma to the product ; and the work
is done. There is nothing further needed except to
mold the still soft chocolate into cakes.

^^Such is the composition of chocolate of superior
quality. But for the cheaper grades demanded by

196 THE SECRET OF EVERYDAY THINGS

the trade it is customary to mix in certain ingredi-
ents of less cost than cocoa, as for example the
starchy constituent of potatoes, corn, beans, and
peas. It is even said — but my faith in the honor of
the manufacturers makes me hesitate to believe it —
that there are so-called chocolates in which not a
particle of cocoa is present. Sugar, potato flour,
fat, and powdered brick are said to be the ingre-
dients.''

*^And that horrid trash is sold?'' asked Marie
incredulously.

** Yes, it is sold ; its low price attracts purchasers."

**If they offered it to me for nothing I wouldn't
take it," Claire asserted. *^What a queer thing to
eat — a cake of brick ! ' '

^*It is never true economy to buy very cheap
things. The manufacturer and the merchant must
make their profit. And yet the buyer is always try-
ing to beat down the price. So what does the manu-
facturer do? He substitutes something worthless
for a part or all of what has real value, and then sells
his goods at whatever price you please. He gives
you something for your money, it is true ; but of tener
than not you are outrageously cheated. You have,
let us say, only a penny to spend on a cake of choco-
late; you will get the chocolate, but it will contain
very little cocoa, or none at all, a great deal of potato-
flour, and perhaps some powdered brick. You think
you have driven a sharp bargain ; in reality you have
been sadly duped. For your penny you could have
bought several potatoes, which would have been a
far better investment, and the powdered brick be-

CHOCOLATE 197

sides, if you really care for that sort of thing. Al-
ways be suspicious of marked-down goods, my chil-
dren; the low price is low only in appearance and
much exceeds the real value of the goods. ' ^

CHAPTER XXXVI

SPICES

HEN we speak of spices we mean those vege-
table substances of aromatic odor and hot
and pungent taste that are used to heighten the flavor
of food and aid digestion. The principal ones are
pepper, clove, cinnamon, nutmeg, and vanilla.

^^ Pepper is the fruit of a shrub called the pepper-
plant. You have often seen those
little round black grains, with such
a pungent taste, that are used for
seasoning certain kinds of food —
sausages for example. Those are
the berries of the pepper-plant just
as the bush produces them.''

*^And do those grains, when they
Branch of PeppT ^rc powdcrcd, givc pepper?'' asked
Plant with Berries Jules ; ^ ' such as wc scc ou the table
every day beside the salt-cellar?"

^'Exactly," replied Uncle Paul. *^The culture of
the pepper-plant is successful only in the hottest
parts of the world, chiefly in two of the Sunda Is-
lands, Sumatra and Java. It is a shrub with a slen-
der and flexible stalk having the form of a runner
and winding around neighboring tree-trunks. Its
leaves are oval, leathery, and shiny; its blossoms
small, grouped in long and slender hanging clusters ;

198

SPICES

199

and its berries, which are no larger than our cur-
rants, are first green, and finally red when ripe.
Pepper is gathered when the bunches begin to turn
red; The harvested berries are put to dry on mats
in the sun, whereupon they soon turn black and
wrinkled, taking thereafter the name of black pepper.

^^As their sharp flavor is chiefly confined to the out-
side integument of the berry, this is sometimes
stripped off in order to obtain a less pungent variety
of pepper. For this purpose the freshly gathered
berries are soaked in water, which makes them swell
and crack their outer skin. After that they are ex-
posed to the sun and, when
dry, all that needs to be
done is to rub them be-
tween the hands and then
fan them to blow away the
exterior covering. This
process gives white pep-
per, which is much milder
than the black.

^'If you examine some-
what attentively a single
grain of the 3pice called
cloves, after letting it soak
some time in water until
it becomes swollen and expanded, you will easily
perceive it to be a flower. Cloves are, in fact, the
blossoms of a tree called the clove-tree, gathered and
dried in the sun before they are full-blown. The
upper part of these blossoms, being rounded like a
button, bears some resemblance to the head of a nailj

Flowering Branch of Clove Tree
and Unopened Bud

200 THE SECRET OF EVERYDAY THINGS

the lower part, which is long and slender, is not
unlike the pointed portion. From this rough re-
semblance comes the name of clove (which is con-
nected with the Latin clavus and the French clou,
meaning a nail).

^^The Moluccas, or Spice Islands, are the home of
the clove. It is a fine tree, about fifteen meters high,
with slender branches, oval and shiny leaves, and
very strong-scented flowers grouped in clusters.

*^ Cinnamon is the bark of a tree, the cinnamon
tree, originally from the island of Ceylon, but now

cultivated in our tropical
colonies. With the point
of a pruning-knife the
bark of the branches is de-
tached in strips, which are
laid together according to
size, a narrower on a
wider strip, and are then
exposed to the sun, where-
upon they curl up like
quills, one within another,
in the process of drying.'*
**From the look of cin-
namon as it is sold by the
grocer,'' said Marie, '*you can easily see that it is
a bark ; but I did n 't know what country it came from
or what tree produced it.''

''From the Molucca Islands, noted as the chief
source of the world's supply of spices, we get, in ad-
dition to cloves, nutmeg, which is now successfully
raised in our colonies. The nutmeg plant is a grace-

Flowering Branch of Cinnamon
Tree

> >

SPICES

201

ful tree which grows nearly ten meters high. In
its rounded head and thick foliage it resembles the
orange tree. Its leaves are large, oval, glossy green
on the upper side, and whitish underneath ; its blos-
soms, small, bell-shaped, and pendent like those of
the lily of the valley, are very sweet-smelling. The
fruit, as large as a medium-sized peach, is composed
of three parts. First comes a fleshy, edible exterior
which at maturity breaks in two ; next to this is a net-
work of slender strands, very bright scarlet in color,
which yields the spice known as mace ; and finally, in
the center, lies the seed, or nutmeg proper, which is
used as spice. This latter is an oval-shaped body
of the size of a large olive, its flesh scented, oily, and
very firm, with reddish veins running through it.

*' Vanilla grows in damp and shady forests in the
coast districts of Guiana
and Colombia. It is a
plant with a slender stalk
that takes the form of a
runner and interlaces the
neighboring branches,
stretching even from one
tree to another, and re-
sembling a small cord cov-
ered with beautiful green
leaves. Its flowers are
large and graceful in
shape, white inside, and
greenish yellow outside.
The fruit, the part to which we give the name vanilla,
is sought for its balsamic, sweet odor and its mild,

Flowering Branch of Vanilla

Plant

a, the fruit.

W2 THE SECRET OF EVERYDAY THINGS

very agreeable taste. It is composed of a viscous
pulp and a multitude of very small seeds. In shape
and appearance it is long and cylindrical, black,
slightly curved, and of the size of one's finger. Va-
nilla is used to flavor custard, whipped cream, and
other similar dishes of which you children never re-
fuse a second helping.''

CHAPTER XXXVII

SALT

«^^ ALT, so necessary for the seasoning of our food,
k3is also very useful as a preservative. The pork
stored away for the winter's use is commonly salted
or smoked, or both, to keep it from spoiling. Beef,
too, is salted do^\^l, especially as an article of food
for sailors on long voyages ; and vast quantities of
fish — cod, herring, haddock, and mackerel — are pre-
served with salt and sent to all parts of the world,
even to the smallest villages remote from the sea-
coast. From these various uses to which it is put
you will readily perceive that common salt is one of
the most valuable of substances.

^'But if we judged of the usefulness of a substance
from the price it commands in the market, we should
fall into the gravest of errors. For example, the
diamond takes highest rank in respect to price, a
price that is nothing short of exorbitant, but for real
use to man, except as an instrument for cutting glass
— and as such it is commonly employed by glaziers —
it stands very low in the scale. On the other hand,
iron, coal, and salt are among the cheapest of sub-
stances, the price per pound being considered, while
at the same time they are infinitely more useful than
the precious stones, which most often serve only to
gratify a foolish vanity. Providence takes no heed

203

204* THE SECRET OF EVERYDAY THINGS

of this false valuation, but has assigned the highest
importance to iron, coal, and salt by scattering them
in profusion all over the earth, and a very inferior
importance to the diamond by relegating it to some
few remote districts in little-known lands, and that
too in very small quantities.

'^Accordingly, salt, like all supplies required by
mankind in general, is very abundant. The sea,
covering as it does three quarters of the earth *s sur-
face, the sea, of such tremendous depth and volume,
holds in its measureless immensity an enormous
mass of salt, since each cubic meter contains nearly
thirty kilograms. If all the oceans should dry up
and leave behind their saline contents, there would
be enough salt to cover the whole earth with a uni-
form layer ten meters thick. ' '

'*What is the use of all that salt!" asked Marie.

''Its use is to preserve the ocean waters from cor-
ruption despite all the foul matter therein deposited
by the countless denizens of the deep and in spite of
the impurities of every kind unceasingly poured in as
into a common sewer by the rivers, those great
scavangers of the continents. ' ^

"They say sea-water is undrinkable, ' ' remarked
Claire.

"I can well believe it,'^ assented her uncle. "In
the first place, it is very salt, and then it has an acrid,
bitter taste that is unbearable. A single mouthful
of this liquid, clear and limpid though it is, would
produce nausea. Hence it cannot be used in prepar-
ing our food, since it would impart its own repulsive
flavor; nor can it be used for washing clothes, be-

SALT 205

cause soap will not dissolve in it and, more than that,
the clothes in drying would retain an infiltration of
salt just as does the codfish you buy at the grocer's.

^^I have already described^ to you how salt is
gathered from salt-marshes with the help of the sun's
heat to dry up the water and leave the crystallized
salt ready to be scraped together and carried away.
Indeed, the sea is an inexhaustible reservoir of salt :
we could never get to the end of it, however lavishly
we salted our food. To supplement this abundance,
the soil itself, the earth, contains in its depths thick
beds of salt which are worked with pick and drill
just as stone for building is worked in the quarry.
This salt that is dug out of the earth is called rock-
salt. It differs from sea-salt only in its color, which
is due to various foreign substances, being most
often yellow or reddish, sometimes violet, blue, or
green. When intended for table use or cooking, it is
purified with water, and then is undistinguishable
from sea-salt.

*^ There are salt-mines in the departments of
Meurthe and Haute-Saone, but the greatest salt-
mine is that in the neighborhood of Cracow in Po-
land. Excavations have there been made to the
depth of more than four hundred meters. The
length of the mine exceeds two hundred leagues, and
its greatest width is forty leagues.

**In that bed of salt are hew^i out great galleries
with loftier vaults, in some instances, than that of a
church, and extending farther than the eye can reach,
crossing one another in every direction, and forming

1 See "The Story-Book of Science."

206 THE SECRET OF EVERYDAY THINGS

an immense city with streets and public squares.
Nothing is lacking to the completeness of this sub-
terranean town : divine service is held in vast chapels
cut out of the solid salt, and dwellings for the work-
men, as well as stables for the horses employed in
the mine, are likewise hewn out of the same material.
There is a large population, and hundreds of work-
men are born and die there, some of them never leav-
ing their underground birthplace and never seeing
the light of the sun. Numerous lights, constantly
maintained, illumine the city of salt, and their beams,
reflected from crystalline surfaces on every hand,
give to the walls of the galleries in some places the
limpid and brilliant appearance of glass, and in
others cause them to shine with the beautiful tints of
the rainbow. What magic illumination in those crys-
tal churches when a thousand candles are reflected hj
the vaulted roof in gleams of light of all colors !''

^^Yes, it must be a magnificent sight,'' Jules as-
sented; ^'but, all the same, I should want to come
up now and then into the light of day.''

*^ Undoubtedly; for with all its splendors that sub-
terranean abode is far inferior to ours. We have the
open air, that pure air with which we delight to fill
our lungs ; and we have the sunlight, a vivifying light
that no artificial illumination can equal. ' '

^^Nevertheless I should like to see that mine," said
Emile. ^^What a tremendous grain of salt, to hold
whole towns ! ' '

CHAPTER XXXVIII

OLIVE OIL

OIL is obtained from seeds of various sorts and
from certain kinds of fruit, but the most highly
esteemed oil for the table, the very queen of oils, is
that which we get from the olive, the fruit of the
olive-tree. This precious tree, which the ancients
made the symbol of
peace, fears the rude
winters of the North and
thrives with us only in
Provence and Langue-
doc, especially in the de-
partments bordering on
or near the Mediterra-
nean. In size it is not a
tall tree, usually attain-
ing about twice the
height of a man. Its
head is rounded, not very ^ ^ ^ .^^ f ^^y^ ^ ^ , .^,

' ' "^ 1, Branch with fruit. 2, Branch with

dense in growth, and fur- ^°^'"^- ""' ^ ^°^'"-

nishing but poor shade ; its leaves are narrow, leath-
ery, of an ashen-green color, and do not fall in win-
ter. In summer its sparse branches are the favor-
ite resort of grasshoppers, which, reposing on the
bark of the tree in luxurious exposure to the intense
heat of the sun, indulge in unrestrained exhibition
of their musical accomplishments.

207

^8 THE SECRET OF EVERYDAY THINGS

^ ^ The olive is green at first. The flesh covering its
hard stone, which is pointed at both ends, has the
most disagreeable taste you can imagine. An unripe
grape is sour, an immature pear harsh, a green apple
tart ; but an olive not yet fully ripened far surpasses
them all in its repulsive flavor. At the very first
bite its unbearable acridity bums the mouth so that
you might think you were chewing a red-hot coal.
Certainly he had need of a rare inspiration who first
reposed confidence in this unpleasant fruit and suc-
ceeded in extracting its oil, which is mildness itself. ^^

*^I once took a notion,'^ said Marie, ^Ho taste of an
olive as it grew on the tree, and I can tell you I soon
had enough of it. Goodness, what a horrid fruit!
How can such sweet oil come from such bitter flesh T^

* * Later when the cold weather of approaching win-
ter comes, in November and December, olives change
from green to reddish, and finally turn black. Then
the skin wrinkles and the flesh ripens, losing its tart-
ness and becoming rich in oil. That is the time for
harvesting the fruit. Women with the help of short
ladders gather it by hand and fill their upturned
aprons, blowing now and then on their fingers, be-
numbed by the piercing cold of the December morn-
ings. The harvest is piled up at the foot of the olive-
tree on a cloth that has been spread there, and the
picking is resumed amid interminable chattering and
bursts of laughter from among the branches.

* * The olives are taken to the mill, where, after be-
ing crushed under vertical millstones, they are cold-
pressed. By this first pressure is obtained fine or
pure oil, the most esteemed of all. Subjected to the

OLIVE-OIL 209

action of hot water and pressed a second time, olives
furnish a second grade of oil. Finally the residue,
mixed with the imperfect olives, such as mndfalls
and those that are worm-eaten, yields what is known
as pyrene oil, which is too ill-flavored to be used in
cooking, but is useful for lighting and for soap-
making. The very last residue is made into oil-
cakes, an excellent fuel.''

'^But it isn't their oil alone that makes olives
valuable," said Marie; ^'they are good to eat after
some sort of treatment that I should like to know
about. ' '

**0 lives that are black, very ripe, and wrinkled,
can at a pinch be eaten just as they come from the
tree, in spite of a slight harshness of flavor that still
clings to them. To remove this they are slightly
salted, sprinkled with a few drops of oil, and kept in
a pot, where they are stirred from time to time. In
a few days they are ready to eat. Sometimes they
are merely soaked in salt water.

*^But however they may be prepared, black olives
are never equal to green ones. The most ill-flavored
olives as they hang on the tree are the best when once
freed of their extremely disagreeable taste. Ener-
getic treatment is necessary to give them the desired
mildness of flavor. Recourse is had to potash, that
harsh substance I told you about in speaking of ashes
and the use of lye in washing. A quantity of very
clean ashes is taken from the fireplace and put into
water, to which is added a little lime, the effect of
which is to increase the strength of the potash.
Finally the clear liquid, charged with the soluble

^10 THE SECRET OF EVERYDAY THINGS

portion of the ashes, is poured over the green olives.
After some hours of contact with this corrosive fluid
they lose their acridity, and all that remains to be
done is to rid them of the lye that impregnates them.
This is accomplished by soaking them in pure water
and changing the water every day until it is colorless
and tasteless. By this repeated soaking nothing that
the ashes had contributed is left. Lastly the olives,
now of a beautifully green color and an agreeable
taste, are salted down in brine, which insures their
preservation and corrects any undue sweetness of
flavor.^'

^^Then it is potash,'^ said Claire, ^Hhat turns the
horrid-tasting fruit into the olives we see on the
table, and that I am so fond of. ' *

*'Yes, it is the potash obtained from ashes, potash

alone, that subdues and soft-
ens the harsh flavor of the
olive. Add this service to
those that the same sub-
stance renders us when it en-
ters into the composition of
soap, glass, and washing-
fluid.

Flowering BrVnch of Walnut ''In the CaSC of the olivC
Tree, with Fruit -^ -g ^^^ fl^gj^ ^f ^j^^ fj.^i|.

that furnishes the oil ; but other forms of vegetation
valued for their oily constituent have this in their
seeds, their kernels. Leading examples are the wal-
nut, sesame, poppy, colza, a kind of turnip called
rape, and flax. Break a dry walnut, take a quarter
of the meat, and hold it close to the flame of a lamp.

OLIVE-OIL

211

You will see it catch fire and bum
with a beautiful white flame which
feeds on an oily juice that oozes out
as the heat increases. Thus we find
there is oil in walnuts. To extract
it, we crack the nuts and take out
the meats, which we subject to
strong pressure. Freshly made
nut-oil is pleasant to the taste and
well adapted to culinar\^ purposes; Sesame

therefore it is much in demand wherever nuts
abound. Unfortunately, it soon turns rancid and it
contracts with age a strong and exceedingly repul-
sive taste.

^* Sesame is an herbaceous
annual cultivated chiefl}^ in
America and Egypt. Its
seeds furnish a sweet oil
having nearly the same
qualities as olive-oil. Se-
same-oil is not sold as such
with us, but I suspect deal-
ers occasionally mix it with
olive-oil, which is much
more expensive.

^'Poppy-heads are full of
very fine seeds which furnish a fairly good oil known
as poppy-oil.'*

*' Poppy-heads will put a person to sleep," ob-
served Claire. ''I remember once somebody made
me drink some poppy-tea to put me to sleep when I
was ill. Poppy-oil ought to make one sleep too.''

Poppy

a, upper part of stem with
flower ; 6 , lower part of plant ;
c, the fruit.

21g THE SECRET OF EVERYDAY THINGS

**It is perfectly true that poppy-heads make a tea
that induces deep sleep. They owe this property to
a substance called opium, which is so powerful that
if you took a dose of it no bigger than a pea it would
act as a deadly poison and put you to sleep forever.
But this formidable substance is found only in the
shell of the fruit, in the envelop of the poppy-head,
and not in the seeds. Hence the oil extracted from
these seeds can be used in cooking without any
danger.

^ ^ Colza and rape are two varieties of turnip culti-
vated principally in the North. The pod-like fruit
contains two rows of fine seeds under two long strips
or valves that open from bottom to top at maturity.
These seeds give colza-oil and rapeseed-oil, which
are used for lighting and also in some of the indus-
trial arts, but are unsuitable for cooking on account
of their otf ensive taste.

^ * Linseed-oil, finally, which is used chiefly in paint-
ing, I have already told you about in one of our
former talks. ' '

CHAPTER XXXIX

THE DOUKLE BOILER

'TTIO avoid the danger of scorching ux.- ^burning on'
J. m cooking food over a fire, the double boiler has
been invented. This insures an equable temperature
in the process of cooking, with no risk whatever that
the temperature will rise above the boiling-point of
water, no matter how hot the fire may be under the
boiler. Into a kettle partly filled with water is fitted
a smaller one with a rim near the top to support it.
The inner kettle contains the substance to be cooked,
and is provided with a lid. There you have the
double boiler. The fire acts directly on the contents
of the lower or outer boiler, heating the water, which
in turn transmits its heat to the upper or inner boiler.
In this manner no excess of heat can by any possi-
bility injure the cooking food, and there is never any
crust of burnt matter found clinging to the bottom of
the vessel in which the food is contained, simply be-
cause no part of that food ever passes the compara-
tively low temperature of boiling water. ' '

*^But if the fire is stirred and more fuel put on,''
objected Marie, ^Hhe water in the under boiler would
get hotter and hotter, and the contents of the other
surely would burn ! ' '

' ' No, my child, there you are quite mistaken. The
water in a kettle or boiler can never pass a certain

213

214^ THE SECRET OF EVERYDAY THINGS

limit of heat, let the fire underneath be as hot as you
please. Suppose we put a saucepan of water on the
fire. The liquid heats gradually and finally begins
to boil. Well, when it has once started boiling it is
as hot as it ever will be. In vain would you stir the
fire and pile on fuel and blow the flame ; your energy
would be wasted. The water would boil faster, it is
true, but it would not become any hotter. '^

^^Do you mean to say,'' asked Emile, ^Hhat a great
bed of red-hot coals would not heat water so that it
would be any hotter than if there were only a handful
of burning sticks under it ? ' '

^'It would make it boil faster,'' was the reply,
**and it would generate more steam ; but I repeat that
the water would not rise a single degree in tempera-
ture when once it had begun to boil. Nothing in the
world can increase the heat of boiling water so long
as the steam is free to escape."

^^It is very strange," commented Jules, ^Hhat a
great fire cannnot make more heat than a small one. ' '

^'Ah, but you must not fall from one error into
another," returned his uncle. ^*A great fire does,
plainly enough, make more heat than a small one;
but this excess of heat is not retained by the water,
and therefore the latter does not become any the
hotter."

^^I should like to know," said Claire, ^^how they
make sure that boiling water cannot get any hotter
than when it first begins to boil, no matter how hot
the fire underneath. They don't put their hands in
to find out, I suppose."

*^ Certainly not. The test is made with a ther-

THE DOUBLE BOILER 215

mometer, the little instrument I have already de-
scribed ^ to you. If a thermometer is plunged into
boiling water the mercury or spirits contained in the
bulb and the lower part of the glass tube will be seen
to rise until the division marked one hundred (centi-
grade) is reached — never more, never less, however
hot the fire, so long as the water is free from any
intermixture of other matter. If the fire burns
furiously the water will boil all the faster and will
send off great volumes of steam ; if the fire is low the
water will boil slowly and send off but little steam;
but in each case, so long as it boils at all, it will be
of exactly the same temperature — one hundred de-
grees centigrade. In this way it is established be-
yond question that freely boiling water can never rise
above a certain temperature, no matter how hot the
fire underneath.

*^The usefulness of the double boiler is thus made
plain to you. The inner kettle, immersed in boiling
water, can never be subjected to a heat greater than
that of boiling water. Now, many substances, espe-
cially those that serve us as food, suffer no injury
from being raised to the boiling-point of water, while
they scorch and acquire a bad taste if heated to a
higher temperature. Such, for example, is the casein
of milk. Therefore in cooking preparations contain-
ing milk, it is well to use the double boiler. And in
melting butter in order to free it from casein and
make it keep better — a subject we have already dis-
cussed ^ — the double boiler is better than a single

iSee "The Story-Book of Science."
2 See "Our Humble Helpers."

216 THE SECRET OF EVERYDAY THINGS

kettle. The casein is deposited at the bottom with-
out risk of burning, and the pure butter is poured off
at leisure and stored in pots or jars, which are sealed
up and kept from year to year without deterioration
of the contents, so far as cooking purposes are con-
cerned. ' '

CHAPTER XL

LITTLE PESTS

THE chief constituent of cheese, as we have al-
ready seen/ is casein, which is separated from
the rest of the milk by the action of rennet. But
casein alone would make very poor cheese, and there-
fore it is customary to add more or less cream to it
and thus furnish a cheese of greater richness and
savor. The amount of cream added determines in
general the richness and palatability of the cheese,
and thus innumerable grades and varieties of this
article of food are offered for our selection ; yet they
all owe their origin to the one substance, milk.

**Kept too long, as I have told you before, all
cheeses, some earlier, others later, become moldy,
first on the outside, then on the inside, the mold being
at the outset of a vellowish white, afterw^ard blue or
greenish, and finally brick-red. At the same time the
substance of the cheese decays and acquires a re-
pulsive odor and a flavor so acrid as to make the lips
smart. Henceforth the cheese is nothing but a putrid
mass which must be thrown away. Deterioration is
more or less rapid according to the softness or hard-
ness of the cheese and its permeability by the air.
To make cheese keep well, therefore, it must be dried
thoroughly and reduced to compactness by strong

1 See "Our Humble Helpers."

217

218 THE SECRET OF EVERYDAY THINGS

pressure. Certain varieties of Dutch cheese, re-
markable for their durability, are so hard and com-
pact that sometimes, before they can be eaten, they
have to be broken up with a hammer and softened by
wrapping in linen soaked in white wine. But, hard
though they are, these cheeses are valued for season-
ing, for which purpose they are first reduced to pow-
der on a grater ; and they are also serviceable in the
provisioning of ships for long voyages.

^^Mold and decay are not the only enemies of
cheese; there are also certain little creatures, mites
and worms, that invade its substance and establish
themselves there, defiling the cheese by their pres-
ence and gnawing it away, little by little. The cheese
mite, or acarus domesticus, as it is called by the
learned, is a tiny creature hardly visible to the naked
eye, with a body all bristling with stiff hairs and
supported by eight short legs. Burrowing with its
pointed head into the soft cheese, it lives there in
colonies of a membership past counting, protected
by the rind and taking shelter in the crevices. As-
sembled in mass, these animalcules look like so much
dust, though on closer inspection it is seen to be ani-
mate dust, moving and swarming, and resolvable into
a prodigious number of extremely small lice. If
these mites are allowed to multiply at their own
sweet will, the cheese gradually crumbles to dust.
To ward off their inroads cheeses should be occa-
sionally scrubbed with a stiff brush and the shelves
holding them washed with boiling water. Cheese al-
ready attacked should first be well brushed and then
rubbed with oil, which kills the mites. A more ener-

LITTLE PESTS 219

getic procedure consists in subjecting the cheese to
the fumes of burning sulphur in a closed box or chest.
The sulphurous gas kills the animalcules mthout in
the least impairing the quality of the cheese.''

* ^ And Avhat about the worms you spoke of f asked
Claire.

^'They are even more to be feared than the mites.
A\Tiat could be more disgusting than a piece of cheese
promenading, so to speak, across one's plate, borne
on the backs of these horrid creatures!"

''Sometimes they are so numerous," remarked
Marie, ''that the substance of the cheese seems
changed into vermin. It must be the decay that
turns the cheese into mites and worms."

"No, indeed, my child; never in all the world does
decay engender vermin. Cheese-mites and cheese-
worms come from eggs laid by other mites and by
the flies into which the worms are finally changed
just as caterpillars are changed into butterflies."

"Then the vermin that we see swarming in all
sorts of decay does not really come from that
decay?"

"Surely not. The decay feeds the vermin, but
never brings it into being. It comes from eggs laid
by various insects, especially by flies that are at-
tracted from a distance by the smell of decay. Thus
cheese-worms finally turn into flies of various kinds
whose lifetime is spent in the open air, often amid
the flowers. When the time comes for laying their
eggs these flies, guided as they are by the sense of
smell, know very well how to find our supplies of
cheese. There they deposit their eggs, each of which

2^0 THE SECRET OF EVERYDAY THINGS

becomes a little worm which later turns into a fly."
*^How about the worms we find in fruit?" asked
Jules. *^Do they too come from eggs?"

*^Yes, all worms, wherever they may be found,
owe their origin to eggs laid by insects ; and never,
bear in mind, are they produced directly by decay.
Let me give you a few examples.

*^Who is not familiar with the cherry-worm?
The cherry itself may be of fine appearance, plump,
dark purple, bursting with juice. Just as you are
about to put it to your lips you feel a certain soft-
ness near the stem, and your suspicions are aroused.
You open the cherry. Pah! A disgusting worm
swims in the decaying pulp. That is enough. Those
fine cherries tempt you no more. Well, that worm,
if left undisturbed, will turn into a beautiful black
fly, the cherry ortalis^ with diaphanous wings crossed
by four dark bands. The insect lays its eggs on
cherries still green, one on each. No sooner is it
hatched than the worm bores a hole through the pulp
and installs itself next to the stone. This orifice is
very small and, more than that, it soon closes up, so
that the fruit inhabited by the worm looks sound.
The worm's presence does not interfere with the
growth and ripening of the cherry, a fortunate cir-
cumstance for the worm, which is thus allowed to
gorge itself with the juicy sweet pulp. When the
cherry is ripe the worm is also fully developed, after
which it leaves the fruit and drops to the ground,
where it digs itself in and waits for the next May,
when it will turn into a fly, lay its eggs on the young
cherries, and die."

LITTLE PESTS

221

Nut-Weevil

a, back view; b, side view.
(Vertical line shows natural
size, including proboscis.)

^^Now I understand," said Marie, '^how the worm
gets into the cherry. I had always supposed it came
in some way from the decaying pulp of the fruit. ' '

*^I will next show you,'^ continued Uncle Paul, ^^a
picture of the insect that in its worm state eats nuts.
It is called the nut-weevil. With its long, pointed
beak it pierces a hole in the
tender shell of the young
fruit, and at the bottom of
this hole, in contact with the
nut-meat, it deposits an egg
which in a few days hatches
a tiny worm. As this worm
eats but very little the nut
continues to grow and the
nut-meat ripens; but the
gnawing goes on. Some time in August the stock
of food comes to an end and the worm-eaten nut
falls to the ground. The weevil itself, its jaws now
robust, bores a round hole in the empty shell and
abandons its early home to burrow into the ground,
where its transformation takes place and the worm
becomes a perfect insect. '^

**I often fiild,'' said Emile, ^^ under the hazelnut
trees in the garden, nuts that look all right at first,
only each one has a little hole in it and no meat in-
side."

^^The meat has been devoured by the nut- weevil,
and the round hole is the door by which the creature
made its exit. ' '

^^ Sometimes," said Claire, ^'when I crack nuts
with my teeth, I bite into something bitter and soft."

n^ THE SECRET OF EVERYDAY THINGS

**Tliat,'^ returned her uncle, "is the worm of the
nut-weevil, crushed by your teeth.''

* ^ Pah ! The nasty thing ! ' ' she exclaimed.

*^And what about the worms we often find in ap-
ples and pears ? ' ' asked Marie.

*^ Those are what are commonly called apple-
worms, or in learned
language, Pyralidoe.
The moth has wings
in two pairs, the
upper being of an
ash-g ray marbled
crosswise with
brown and adorned
/^ at the wing-tips with
a large red spot sur-
rounded by a gold-
en-red band; the
lower of a uniform
brown. As soon as
the fruit begins to

^_ d, pupa; f, f, ^ , .

^l^^a^^!""'^ if 1bo;r"t;i.;\atKa?"size1 ^ O™ ^hc mSCCt kyS
b. d. more enlarged; c, highly magnified. ^^^ ^^^ -^ ^^^ ^j^g_

som-end of the apple or pear, either fruit being alike
acceptable. The tiny worm that hatches out, no big-
ger than a hair, bores into the fruit and establishes
itself near the seeds. The little orifice by which it
entered soon heals over so that the apple or pear
appears sound for some time.

"Meanwhile the worm goes on growing in the lap
of plenty. It makes a hole communicating with the
outside, to admit fresh air and insure the ventilation

Apple-Worm
a, moth; 6. larva; c, eg£

LITTLE PESTS ^23

essential to the sanitary condition of its abode with
all its encumbrance of rubbish and excrement. By
this tunnel bored through the pulp of the fruit till
the outside is reached the worm both receives fresh
air and from time to time ejects, in the form of red-
dish wormhole-dust, the pulp gnawed and digested.
Apples and pears thus infested do not cease to grow;
on the contrary they mature even earlier than the
others, but it is a sickly maturity, and hastens the
fall of the fruit. The worm in the fallen apple or
pear leaves its domicile by the exit already prepared
and withdraws into a crevice in the tree's bark, or
sometimes into the ground, where it fashions for it-
self a cocoon of silk mingled with bits of wood or
dead leaves ; and the next year it turns into a moth,
at the season that brings forth the young apples and
pears in which are to be laid the eggs for a new
generation of worms.*'

CHAPTER XLI

FLIES

HESE examples," Uncle Paul resumed, ** which
I could multiply indefinitely without finding
a single exception, prove to you that all vermin
swarming in decayed matter owes its origin to eggs
laid by insects, flies, moths, butterflies, and beetles,
of various kinds. Life always springs from life,
never from decay. ' ^

*^A11 the same,'' Marie declared, ** there are lots
of people that say rotting matter breeds worms. "

**That is an error as old as the world, and even in
our day it is widely disseminated, though much less
so than in ancient times. Persons of the highest
education used to regard it as beyond question that
mud, dust, excrement, and other matter in decompo-
sition would breed animal life, even rather large
specimens, such as rats, frogs, eels, snakes, and many
others. If the learned men of antiquity endorse in
their works such gross errors, what must have been
the beliefs of the uneducated!"

*^ Did n't those learned men know," asked Claire,
^Hhat frogs come from tadpoles hatched out of eggs
laid by other frogs ? ' '

* * They did not know it. ' '

* * They had only to look into a pond to find it out. ' '
*^They did not know how to look. In those old

224

FLIES

225

days men reasoned a great deal too much, sometimes
to the point of unreason; but seldom did they take
it into their heads to examine things as they really
are. Patient observation, mother of all our knowl-
edge, was unknown to them. They said, 'That is it,'
without examining the matter, whereas in our day we
examine before saying, ^That is it.' By this re-
versal of method science has, in scarcely a century,
attained to a degree of power that astonishes us
with its marvelous achievements. It is observation
that has given us the means of protecting ourselves
from the thunderbolt by
using the lightning-rod; of
covering enormous distances
in a short time with the help
of steam, which propels the
railway locomotive; and of
transmitting thought in-
stantly from one end of the
world to the other with the
electric telegraph. Truth is
acquired through observa-
tion ; man does not invent it,
but has to seek it laboriously, and is fortunate if he
finds it.

*'For want of close observation the ancients, on
seeing a litter of young mice come out of some hole
in the wall, attributed the procreation of these ani-
mals to the dust of the w^all. If they saw a company
of frogs leaping about on the muddy banks of a pond,
that was enough to make them believe frogs sprang
from mud fermenting in the sun. ' '

Tadpoles

A, B, with gills; C, more ad-
vanced, a, eye; o, enr; m,
moutb : 71, nasal sacs: d, oper-
cular fold; kh, ki, gills; ks, a
single branchial aperture; z,
horny jaws; «, suckers; y, ru-
diment of hind limbs.

226 THE SECRET OF EVERYDAY THINGS

**And I/' declared Emile, ^^am sure they are
hatched out of eggs. From one of these eggs comes
first a tadpole, which little by little loses its tail, gets
four legs, and finally turns into a frog. That is
something like the change of form of a caterpillar
into a butterfly. ' '

^^You know what was unknown to a great many
wise heads in olden times.''

**If I know it, it is thanks to Uncle Paul; and those
who think worms come from decayed matter and
frogs from mud apparently have no Uncle Paul. ' '

^^Alas, my child, how many there are that have
none ! By that I mean there are few who receive the
thorough education that enables one to judge things
from experience, observation, and sound reason.
People trust the merest appearances and transmit
their own premature conclusions. It is least trouble-
some and the quickest way. As you grow older, my
dear children, you will learn how many foolish say-
ings gain currency in the world because people will
not take the trouble to reflect and observe — observe
with their own eyes.

^'If one is but willing to learn, for example, that
the worms in decaying matter come from eggs and
not from the decay itself, all that is necessary is to
have eyes and use them ; for the simplest sort of ex-
periment will decide the question, though it was cen-
turies and centuries before any one thought of it.
We merely cover with gauze or a fine wire screen any
food that is beginning to spoil, such as cheese on the
point of going bad, or anything else of the sort. At-
tracted by the odor, flies soon come circling about

FLIES 2^7

these tainted substances, and even lay their eggs on
the gauze at the points nearest to the decaying matter
which lies just out of their reach. Under these con-
ditions, however far advanced the state of decompo-
sition may be, no worms will make their appearance
in the tainted food, because it has been kept where
no eggs could be laid in it. But if the protecting
gauze or wire screen is removed the flies will lay,
here and there on the decaying substance, piles of
little white eggs, and very soon there will be thou-
sands of worms swarming amid the decomposing
organic matter.

**By means of observations requiring rather more
care it is possible to catch in the very act the little
insect that lays in the cherry the egg from which
comes the worm we all know so well. It has been
ascertained that wormy fruit owes the inhabitants
that devour it, not to decay as such, but to eggs de-
posited there by various insects. It has been dis-
covered that lice do not come from flesh, nor fleas
from fermenting excrement, and also that frogs are
not engendered by pond mud. In short, a thousand
errors of this kind have been so completely refuted
that there remains not the shadow of a doubt on the
manner in which the smallest grub is brought into
being. Wherever you find worms, caterpillars, in-
sects, be assured that other insects have laid their
eggs there. Always and everywhere life owes its
existence to life.'*

*^You open new views to us, Uncle,'' said Marie,
'*and they will rid us of ever so many false notions.''

^^I have merely been trying to show you the salu-

228 THE SECRET OF EVERYDAY THINGS

tary part our reasoning faculties are called upon to
play. It now remains for me to give you a lesson
from established facts. Certain articles of food used
by us, such as cheese and meat, especially game, are
always in danger of falling a prey to worms. This
odious class of vermin owes its existence to flies
which, according to their species, go in quest of ani-
mal flesh or of cheese wherein to lay their eggs.
Two species are already well known to you. for you
often see these flies buzzing noisily on the window-
pane. The first kind is dark blue, the second grey
with reddish eyes. Both of them have much larger
bodies than the ordinary fly, and both attack meat.
As to cheese-flies, I need only remind you of the
worms too common to be unknoA\Ti to you.

*^ These flies, these winged pests and audacious

\ / ^^ parasites — in them

lA ^^\ ^ ( gpH you behold the enemy

W \ M X ^0 ^^^^^ must be kept at a

L| ^^^^^^^^^ distance and prevented

'''^^^ i/b V\ from laying eggs in

^^"^^^ / \ 9 / \ 3 fii ^^^ provisions if we

II / / \ \ W wish to guard our

/ \ larders from the inva-

Hessian Fly g^on of VCrmiu. Cut

a, larva ; b, pupa ; c, infested stalks of i i n i

wheat. cheese should, accord-

ingly, be kept under a bell-shaped wire screen
or, better, under a glass dome, which at the same
time insures its protection from flies and keeps it
from drying up through prolonged exposure to the
air. As to meat and game, which need a continual
circulation and renewal of air, they should be hung in

FLIES 229

cages of fine wire netting, and every time the cage
is opened care should be taken not to let in any of
the blue flies that are usually lurking in the neigh-
borhood. If the enemy were shut up with the pro-
visions even for twenty-four hours, everything would
be spoiled, such a multitude of eggs does the blue fly
lay, and in so short a time. In a securely closed and
carefully watched cage, game, however strong its
flavor, will always be free from worms unless they
were already in the game when it was placed in the
wire cage.^^

CHAPTER XLII

THE THREE STATES OF MATTER

STONE, a piece of wood, a bar of iron, are ob-
jects more or less hard which offer resistance
to the finger and can be grasped and handled. Cut
or chiseled into any desired shape, they will retain
that shape. On account of these properties we say
of stone, wood, iron, and other substances that re-
semble them in this regard, that they are solid sub-
stances.

^^In everyday language this term * solid' is applied
to any object that offers great resistance to rupture,
to deformation. For example, we say *This piece
of wood is solid,' *This iron hook is very solid.'
That is not the way the word should be understood
in the present connection. I call solid any substance
that can be grasped and handled, any substance, in
short, that keeps the shape given it. Thus butter,
tallow, moist clay, are plastic substances readily
molded by the hand into any desired shape. We can
grasp and handle them without difficulty, can fashion
them as we please. In this sense they are solid sub-
stances no less than marble and iron, which are so
resistant."

^ * That is easy to understand, ' ' said Claire. ' ' Any-
thing that can be handled, even if softer than butter,
is called solid. So water is not solid, for I can't

230

THE THREE STATES OF MATTER 231

take up a pinch of it in my fingers as I do with sand.
Neither can I shape some of it in the form of a nine-
pin, for example, and stand it up; or at least I
can't unless I put it in a bottle."

^ ^ Golden-tongue could not have said it better. No,
water is not solid. It slips through the hand that
tries to hold it; it flows. Left to itself it has no
shape, and it is impossible to give it a definite one
except by enclosing it in a vessel. Then it adapts
itself to the form of the container, taking its exact
shape — round if the vessel is round, cubical if the
vessel is a cube. Water and other substances that
flow are called liquids. ' '

^^Then milk, oil, wine, vinegar, melted butter, are
all liquids, '^ said Jules.

**Yes, they are liquids the same as water.

*^Now let us turn our attention to the steam that
escapes from a boiling pot or, if you like, to the beau-
tiful plume of white vapor that comes in puffs from
the smoke-stack of a locomotive as the latter moves
along on the iron rails. You remember those mag-
nificent puffs ascending in billows that remind one of
the softest kind of swans ' do^^^l. ' '

^'I know ^that you mean,'' Emile hastened to re-
ply; ^'the engine puffs them out with a loud noise
like a person blowing with all his might."

^^Well, those white puffs are steam from water,
just like the white puffs from the little boiling pot.
This steam makes the locomotive move, and then,
after it has done its work, it escapes with a loud noise
into the air. Here we have another substance im-
possible to grasp ; and this impossibility is greater

^32 THE SECRET OF EVERYDAY THINGS

even than in the case of water. Handling it is quite
out of the question. Moreover, it expands in all
directions, gaining in volume and occupying an in-
creasing amount of space. On issuing from the
smoke-stack the puif of steam had a certain volume,
not very large. Inside the engine it had still less,
and that is precisely what gave it its force ; for, like
a spring that possesses more energy the more it is
pressed down, steam owes its power to the fact of
its confinement within a restricted space. Once set
free, it gains more and more volume until at last it
becomes so dispersed as to be invisible. You must,
in fact, have noticed that the white plume soon melts,
as it were, in the air and disappears.

*^ Invisible though it thus becomes, it is clear that
this steam exists and that it belongs to a special class
of material substances. Is not air itself intangible
and invisible ! And yet can one doubt its materiality
when, as wind, it is set in violent motion and makes
the trees rock and sway, or even tears them up by
the roots I Thus we perceive there are substances
characterized by an extreme thinness, the thinness
of the air we breathe. These substances do not re-
tain any fixed form like solids ; they have no constant
volume like liquids ; they expand in all directions and,
unless confined, occupy more and more space. They
are called aeriform substances on account of their
resemblance to air; they are also known as gases and
vapors. Air is a gas. To this class belong also the
invisible but pungent fumes of burning sulphur, and
the greenish substance of unbearable smell whose
properties I described to you in our talks on coloring

THE THREE STATES OF MATTER 233

matter and on ink in particular. The first-named
substance is sulphurous oxide, useful in bleaching
wool and silk; the other is chlorine. Lastly, the in-
visible steam from boiling water is also a kind of gas,
or rather a vapor, for gas and vapor are much alike. ' '

^* And that kind of air full of something that comes
from burning charcoal, that dangerous air that gives
ironers a headache if they are not careful to keep
their heaters under a chimney — that must be a gas
too ? ' ' This query came from Claire.

^'The deadly substance emitted by burning char-
coal is in truth a gas, as invisible and as odorless as
air itself. It is called carbonic oxide.

''Thus all substances, or, to use another term, all
bodies, assume one or other of the three different
forms known as the three states of matter; namely,
solid, liquid, and gaseous.

''Now the same substance can, without changing
its nature in the least, become in turn solid, liquid,
and gaseous, according to circumstances. It is
mainly heat that effects these transformations.
Heated to the requisite temperature, certain solids
become liquid ; with still more heat the liquid becomes
a gas. In losing heat, on the other hand, that is to
say in cooling, a gaseous body passes successively
from the gaseous to the liquid state, and from that
to the solid. The following example will show this
more clearly than any mere description.

"Ice is a solid body; many stones are no harder.
Let us put it on the fire in a vessel. It wdll melt ; in
gaining heat it will become liquid water. If this
water in its turn is heated still more, it will begin to

^34* THE SECRET OF EVERYDAY THINGS

boil and will pass off in vapor ; that is to say, it will
take the gaseous state. Here, then, we see water
changing, under the action of heat, from the solid to
the liquid state, and from the liquid to the gaseous.
Most bodies are subject to similar changes. It is
true that sometimes heat of extreme violence is
needed; thus iron will not melt unless subjected to
the intense heat of the blast-furnace ; and to vaporize
the smallest particle of it requires the most tremen-
dous sort of fire that science can produce. And so
with varying degrees of reluctance all elemental sub-
stances obey this common law : heat first melts them,
makes them become liquid, then volatilizes them,
that is to say reduces them to vapor.

^^What does cold do on its part? First take notice
that cold has no real existence, that it is not some-
thing opposed to heat. All bodies without excep-
tion contain heat, some more, some less, and we call
them hot or cold according to whether they are
warmer or colder than we. Thus heat is everywhere,
and cold is only a word that serves to designate the
lesser degrees of heat. To cool a body is not to add
cold to it, there being no such thing as cold ; it is tak-
ing heat away. If a body gains heat it becomes
warm ; if it loses heat it turns cold.

^^Well, then, the act of cooling, that is to say the
withdrawal of heat, restores vaporous bodies to the
liquid state, and liquids to the solid state. Thus the
steam from the boiling pot on coming in contact with
the cold lid loses its heat and turns to water again ;
and the vapor in our breath, when it touches a pane
of glass, becomes cold and runs do^vn in fine drops.

THE THREE STATES OF MATTER 235

Water in its turn if sufficiently cooled turns to ice,
that is to say becomes solid. Other substances act
in the same way: a diminution of heat brings them
back from the gaseous to the liquid state, then from
the liquid to the solid. ' '

CHAPTER XLIII

DISTILIATION

BY the action of heat liquids are vaporized, and
the vapor in its turn becomes a liquid again on
cooling. Suppose, now, there is a mixture of two
liquids of which one turns to vapor more easily than
the other. On the application of heat, with the ex-
ercise of a little care, the more easily vaporized of
the two liquids will be the first to evaporate ; and if
this vapor, instead of being allowed to escape into
the air, is held confined in a cool receptacle, it will
return to the liquid state. In this manner the two
mingled liquids will be separated, the one less easily
vaporized remaining in the vessel used for heating
them, the other being collected in another by itself.
This operation of separating the two is called dis-
tillation.

^^ To fix this process well in mind, let us take an
imaginary example. Let us suppose we have a quan-
tity of water into which has been poured a consider-
able portion of ink. The liquid therefore is black,
unfit for drinking and unfit for any other purpose
requiring the use of water. ' ^

* ' But who would ever dream of drinking water as
dark as shoe-blacking," Claire interposed, ^*or of
using it to wash linen or cook vegetables?''

*^ Nevertheless let us see if there is n't some way to

236

DISTILLATION 237

restore this water to its original purity, to separate
it from the dark pigment in the ink and make it as
clear and limpid as ever. Yes, there is a way: it is
the method adopted in distillation. Water is easily
vaporized, whereas the coloring matter in the ink is
vaporized with extreme difficulty. If, then, we apply
heat the water alone will rise in the form of vapor,
while the dark matter will remain behind. Thus
heat will bring about a separation that at first seemed
impossible. All we have to do now is to confine the
water-vapor and cool it until it returns to the liquid
form ; then the process is complete and we shall have
in one vessel perfectly clear water, in another a tur-
bid liquid containing the ink.''

^'If you had asked me," said Clair, *Ho separate
the two, the water and the ink, after they had once
been mixed, I should have said it could n 't be done.
And yet how easy it is ! We heat the mixture and
the separation takes place of itself. I should like
to see this curious experiment."

** Nothing would be easier than to show it to you
if we had the necessary apparatus. All that I can
do at present is to show you a pic-
ture here that will help to make
the process clear. We put the

darkened water into a glass VeS- Retort (a) and Re-
ceiver ( b )

sel called a retort, which expands
at one end into a large globular flask, and at the
other contracts into a long, tapering neck. The flask
of the retort, when in action, is placed over a fire
or flame."

^38 THE SECRET OF EVERYDAY THINGS

^^Can glass be used for boiling water?'' asked
Jules.

^^ Certainly, if it is thin enough to expand uni-
formly when placed over the fire. The glass in this
instance is of a quality that will bear heat if proper
care is exercised in conducting the operation. Owing
to its transparency it affords a clear view of what
takes place inside, a circumstance of great impor-
tance when we desire to follow the successive steps of
an experiment. The neck of the retort is inserted
into another receptacle, likewise of glass and globu-
lar in shape, which is plunged into cold water. If
heat is applied beneath the flask the water contained
in it is vaporized, while the coloring matter is not.
This vapor, as fast as it reaches the cooling recepta-
cle, immersed as the latter is in cold water, loses its
heat and returns to the liquid state. Thus we obtain
perfectly clear water, free from all traces of ink.
Spring- water is not clearer or purer; indeed, it is
less pure, as you will presently perceive.''

^^That 's all very clever and very interesting," ob-
served Jules, ^^to be able to get clear water out of a
bottle of ink; but what 's the good of it? No one
would ever think of such a thing as blackening water
with ink just to turn it back into clear water by dis-
tilling it. ' '

< i Very true, ' ' was the reply. * ^ I chose that exam-
ple in order to make the process more striking to
you. But if it is not our practice to obtain pure wa-
ter for daily use by distilling it from a mixture of
ink and water, it is no unusual thing to distil ordi-
nary water, and for this reason : however clear and

DISTILLATION 239

g'ood to drink water in its natural state may be, it is
never strictly pure. Whether it comes from a well, a
spring, a river, or a lake, it has been in contact with
the earth and consequently must contain, in however
small a quantity, some of the soluble constituents of
the soil. Would not water be salt if it ran over a
bed of salt, and would it not be sweet if it ran over
a bed of sugar? In like manner water that washes
the soil is charged with the numberless soluble sub-
stances contained therein. Who has not noticed the
earthy deposit left in course of time by even the best
waters on the inside of bottles and pitchers and, in a
still more marked degree, of water-pipes? What
is this deposit except an incrustation gradually
formed by the foreign substances dissolved in the
water? No water, then, that comes in contact with
the soil is pure, in the strict sense of that word.
Eain-water, even when collected before it has reached
the earth or washed the roofs of houses, is neverthe-
less impure; for it contains particles of dust swept
do^vn in its descent. I leave out of the account
muddy water that owes its turbid condition to pelt-
ing rain or driving storm, also sea-water with its in-
evitable mixture of salt and its repulsiveness to the
taste. Suffice it to say that all water in its natural
state and containing however slight an admixture of
foreign substances is unfit for certain manufacturing
purposes, for example certain delicate operations in
dyeing. Very often water may be most excellent for
drinking, exactly suited to domestic uses, so irre-
proachably clear that the sharpest eye can detect in
it no alien substance whatever ; and yet for such pur-

240 THE SECRET OF EVERYDAY THINGS

Still

poses as those I have indicated it may be worthless.
^'To give water the purity required in certain of
the arts it is customary to distil it, not with an ap-
paratus of glass, such as we use for a simple experi-
ment like the one we have just been considering, but
with a more substantial, more capacious outfit. The
water to be purified is poured into a copper boiler, or

alembic, or cucurbit,
as it is variously
called, which is some-
times provided with a
hot-water jacket, and
sometimes is placed
directly over the fire.

o, alembic; &, hot-water jacket; c, head;

d, rostrum or beak; e, worm; /, refrigera T'lio cfocnn QC/^anrla in

tor; h, h', tube for conveying away the ^^^^ teLt^dm dbCeilUb LU

warm upper stratum of water heated by the ^ ^^^^ ^^ ^^^^^ ^^

head, surmounting the boiler, and thence by a long
neck, called the rostrum or beak, it reaches a metal
tube coiled in a spiral and hence known as the worm.
This latter is immersed in cold water contained in
what is called the refrigerator. In circulating
through the worm the vapor becomes chilled and is
condensed into water, which runs out at the lower
and free end of the worm, the latter passing through
the side of the refrigerator at its base.

**It is plain that the water in the refrigerator must
gradually become heated by the steam circulating in
the worm, and thus be rendered unfit for condensing
purposes. Hence it must be renewed from moment
to moment, and this renewal is in fact made to go on
continuously. Fresh water is run into the funnel
shown in the picture as reaching to the bottom of the

DISTILLATION Ml

refrigerator, while the warm water, being lighter
than the cold, rises to the top and runs out through
the tube also shown. There is thus a constant re-
newal of cold water at the bottom of the refrigerator,
with an equal outflow of warm water at the top. At
the end of the operation there is found in the bot-
tom of the boiler a muddy paste representing the im-
purities contained in the water subjected to distil-
lation.

''Nothing is more disagreeable than to gulp do^vn
by accident a mouthful of sea-water. Nor is this
water any better for washing linen than for drinking,
since it will not dissolve soap ; and it is equally un-
suited for purposes of cooking. But by being dis-
tilled the water of the ocean, so unfit for our use in its
natural state, becomes purified. Great ocean steam-
ers are provided with distilling apparatus in which
sea-water is freed from its salt, and the resulting
liquid differs not a particle from that obtained by
distilling fresh water. It is suitable for cooking and
washing, but not the best kind of water to drink,
because it holds in solution no air, a little of which
is needed in all drinking-water. But it can be made
to absorb the lacking ingredient by being shaken up
in contact with the air. ' '

CHAPTER XLIV

WATBB

^^rriHE water that we use every day is hardly ever
J. pure. However clear it may be, it always con-
tains certain foreign substances in solution, as is
proved by the slight coating of earthy matter that

. forms little by little on the inside of our water-bot-
tles, tarnishing the glass and lessening its trans-
parency. ^ '

^^That earthy coating is very hard to wash off,'*
remarked Marie. ^'I remember one day I tried and
tried to get it off with water alone, but it seemed to
have become a part of the glass itself.''

^^Yes, that coating sticks so fast just because it is
of stony matter, of veritable stone such as the mason
uses for building our houses. It is not at all sur-
prising, therefore, if mere washing with water fails
to remove it. To make it let go its hold it should be
dissolved in an acid, vinegar for example, or lemon-
juice. Pour a little vinegar into a carafe and shake
it up until it has wet all the clouded part of the glass ;
you will see the stony coating dissolve, creating a
little foam as it does so. AVhen the acid has done
its work, wash it off with water, and you will find
that all the foreign matter comes away with it, leav-
ing the glass once more as clear and transparent

as ever."

242

WATER 243

^^Then even the clearest water, '^ Jules observed,
^' water in which the eye can detect nothing, abso-
lutely nothing, nevertheless contains dissolved stone,
just as sweetened water contains sugar invisible to
the eye ; and when we drink a glass of water we drink
with it a little of this stony matter. Who would
ever suspect it!"

**It is very fortunate, my dear boy, that we do
thus drink a little of this dissolved stone. Our
bodies, in order to grow and become strong, require
a certain proportion of stony matter for the forma-
tion of our bones, which are to us what its solid
framework is to a house. This needed matter we
cannot by any possibility create by ourselves; we
must get it from our food and drink. Water, for
its part, furnishes a good share, and if it did not
contain the required mineral matter we should re-
main puny and ailing, being unable to attain our nat-
ural size.'^

^*Is there much of this dissolved stone in the water
we drink r^ asked Emile.

*^To be fit for drinking, water must contain a lit-
tle, for the reason I have just explained ; but when it
contains too much it is hard to digest and burdens
the stomach. The right proportion is from one to
two decigrams for a liter of water ; or, in other words,
about as much as you would take up between your
thumb and forefinger. Any considerable excess
makes the water heavy, as we say, because it weighs
on the stomach.

*^ Certain waters are so rich in dissolved stony mat-
ter that they quickly encrust anything they touch.

M4^ THE SECRET OF EVERYDAY THINGS

Such is the water of the celebrated spring of Saint
Allyre at Clermont-Ferrand. It is made to fall upon
a heap of tree branches which break up the water and
divide it into spray. This fine shower is allowed to
fall on objects that it is desired to coat with an in-
crustation of stone — on birds ' nests, baskets of fruit,
bouquets of flowers, and foliage. A layer of stony
matter is soon deposited by this mineralized dew, and
the birds' nest, the basket of fruit, the bouquet are
turned to stone, or, more exactly, they are overlaid
with a coating of stone, so that one would say a
sculptor's chisel had deftly cut these objects out of
marble. Such water, needless to say, is unfit for
drinking. ' '

^'I should think so!'' cried Claire. *^It would
pave the stomach with marble, which would not be
very good for the digestion."

''Never does the water such as we use," Uncle
Paul continued, ''have anything like that super-
abundance of stony matter, though it often does con-
tain enough to cause difficulty in certain domestic
operations, especially laundry-work. You must have
noticed how the water in which clothes are washed
with soap always turns more or less white ; perhaps
you have even observed that little flakes or clots of
whitish matter are formed in the water and float
about in it."

"Yes, I know what you mean," Marie hastened to
reply; "and when there are too many of those white
clots it is hard to get any suds; the soap is just
wasted."

"Well, now you will know that the white tinge and

WATER 245

the floating particles are caused by the presence of
dissolved stony substances. Perfectly pure water,
distilled water, takes up soap without losing its clear-
ness, or with very little loss ; it does not turn white,
it does not form flakes. To convince yourselves of
this, try a little rain-water some day for washing out
a piece of linen ; for rain-water is almost as pure as
distilled water. You will see how easy it is and how
the soap does its work without waste. There will
be no white particles left in the water, though there
will be plenty of lather, and no whitish tinge to the
water under the foam such as you commonly see in
wash-tubs.

*^ When water turns very white under the action of
soap and shows abundant flakes, it is a sure sign of
too much stony matter in the water. Laundry-work
then becomes difficult and soap gives trouble about
dissolving, dissipating itself in tiny clots without
acting on the soiled linen. Such water is also bad
for drinking, overburdening the stomach with its ex-
cess of mineral matter. The water found in regions
rich in limestone is liable to this objection."

**I can see well enough,'^ said Emile, "that a little
stony substance in the water must be a good thing
for us, and I also see how troublesome too much must
be. The stomach would soon get tired of digesting
stone. '^

''Finally,'' his uncle continued, ''hard water like
that is unfit for certain culinary purposes, partic-
ularly cooking vegetables such as green peas, and
chick-peas — the last named especially. The mineral
matter in the water becomes incorporated with the

me THE SECRET OF EVERYDAY THINGS

vegetables and then, no matter how long you boil
them, they will not become soft/'

*^Yes,'' said Marie, ^'I know how chick-peas act
sometimes: after hours and hours of cooking they
are just as hard as at first and will bound like mar-
bles if you throw them on the floor. What prevents
their softening, you say, is the stony matter dissolved
in the water."

*^That, and nothing else. Now, since all water
contains more or less of this, we are often troubled
about cooking the vegetables I have named. But
there is a simple remedy that I recommend in all
such cases: drop a little pinch of potash into the
water, and the most obstinate beans or peas will
cook to perfection, even the chick-pea itself soften-
ing to a mush. ' '

^^ Without getting any bad taste I" asked Marie.

^^ Without getting any bad taste or anything else
that need be feared, on condition, however, that the
potash be used very sparingly — ^just a pinch and no
more.

**But there is another way to use it that is more
readily at our command. Since potash is obtained
from wood-ashes it is plain that wood-ashes can here
play the part of potash. In a small piece of cotton
cloth folded two or three times tie up a thimbleful
of clean ashes, and drop this into the pot with your
vegetables. The potash in the ashes will dissolve
and permeate the water, while the earthy matter will
be left in the cloth, which is to be taken out when the
vegetables are done. By this means, however hard

WATER 247

the water, you will get the better of the most re-
fractory peas and beans.''

'^ Uncle Paul is always finding some new use for
wood-ashes," remarked Claire; "and now we see
that they will soften even the hardest of chick-peas."

CHAPTER XLV

WATER (continued)

'T ^TATER may be clear, colorless, fresh, agree-
T V able to the taste, excellent for washing and
cooking, and nevertheless, with all these admirable
qualities, dangerous to drink. This danger arises
from microbes in the water, though nothing betrays
their presence, neither smell nor taste, nor any lack
of clearness, nor the least impairment of the water
for household uses. Since certain kinds of these in-
finitesimal organisms cause serious maladies, we im-
peril our health by taking them into our bodies in our
drink. Water, therefore, to be good to drink, should
contain no microbes. One well may furnish water of
irreproachable purity, while another may be more
or less infected with microbes and hence pernicious
and dangerous despite all appearances to the con-
trary.

^^ Where, then, are we to look for perfectly pure
water, water that we may drink without thought of
danger? It is furnished only by springs. Let us
dwell for a moment on the origin of springs, and we
shall then understand why spring-water is pure.
Rain, melting snow, the dampness of night fogs, soak
into the ground, especially on mountain slopes ; and
the water thus absorbed over large expanses of sur-
face sinks to a great depth, collects in little under-

248

WATER 249

ground streamlets, makes its way through opposmg
soil and sand, also through the cracks in rocks, and
comes to the surface again in some distant valley,
welling up through a fissure and producing a spring.

^^From its starting-point to its destination the wa-
ter thus passes through a sort of filter of enormous
thickness, kilometers thick in fact, and at a sufficient
depth to be free from surface defilement. By pass-
ing through successive beds of clay, marl, sand,
crumbling rock, and joorous stone, the water grad-
ually rids itself of its impurities and leaves them be-
hind, so that on reappearing above ground it no
longer contains any corpuscles even of the micro-
scopic minuteness of microbe germs. Spring-water
is pure by virtue of the thorough filtering it has un-
dergone, a filtering such as no means at our disposal
could begin to achieve.

^ ' Can we say as much for the purity of river- water
and brook-water? Far from it. These streams, es-
pecially in the neighborhood of large cities, receive
frightful quantities of foul matter. Into them empty
sewers charged with the refuse from streets and
dwellings ; in their waters are washed the garments
we have soiled and the foul linen that has served as
bandages for sores; their channels are choked with
all sorts of decaying matter from many factories.
It is therefore evident that river and brook, how-
ever clear their water, cannot furnish us with a
drink that is free from suspicion. Microbes abound,
and those of cholera, for example, may be among
them, from the person of some victim to that dis-
ease or from the linen used in his treatment.

^50 THE SECRET OF EVERYDAY THINGS

*^Not even a country brook is void of offense.
Eain-water washes the tilled fields, soaks through
the manure spread as fertilizer, and carries to the
stream the harmful germs that breed in all decay.

^^ Well-water, besides being not always sufficiently
aerated, is likewise subject to defilement. In the
first place, owing to its slight depth, a well becomes
charged with water from the upper layers of the
soil, a filter not thick enough to arrest injurious
germs. In the second place, wells in towns are dug
in ground that has become defiled to a considerable
depth by the prolonged sojourn of man. Not far
away are drains and sewers and other repositories of
filth, from which it is very difficult to safeguard the
wells.

*^In the country the danger is less, provided the
well be covered so as not to admit any dead leaves or
the dust raised by the wind ; and provided especially
that the well be at a distance from all stables, dung-
heaps, deposits of compost^ and other sources of in-
fection through infiltration.

^^Mere taste and appearance make us reject for
drinking-purposes all water that repels by its odor,
its taste, or its lack of clearness. But this is not
enough. It is now established beyond doubt that
certain diseases, especially typhoid fever and
cholera, are propagated by water containing their
microbes. Suspicious as we must at all times be of
river-water and well-water, in periods of epidemic
we should exclude them entirely from our use and
have recourse to spring-water alone.

''But not every one can obtain spring- water.

WATER 251

What shall be done in such cases? The answer is
simple. We have seen that the temperature of boil-
ing water kills all living creatures. Eiver-water
or well-water can accordingly be rendered quite fit
for all our uses on the express condition that it be
first boiled. Freed of its noxious germs by heat, it
is thenceforth harmless.

^^ Summing up these points in a couple of precepts
of prime importance to our health, we may say:
Keep all wells and springs free from filth, and when
cholera is prevalent use no well-water or any water
from river or brook without first boiling it."

CHAPTER XLVI

VINEGAR

* \7'0J] will be surprised to hear, ' ' said Uncle Paul,

A ^Hhat any sweetened substance will generate
alcohol by a remarkable chemical change called fer-
mentation, and that alchohol in its turn changes into
vinegar. As sugar is the origin of alcohol, it is
sugar, in reality, that makes vinegar. Here we see
something generating its opposite, sweet giving birth
to sour.''

^'The same thing happens," Marie observed,
* ^ with milk or with a slice of melon : they both sooner
or later lose their sweet taste and turn sour.

^* Those are two good examples of substances
which, at first sweet, turn sour as soon as decomposi-
tion sets in; but vinegar such as is used in cooking
goes through a little different process ; for it comes
not directly from sugar but from alcohol. All al-
coholic liquids are good for making vinegar ; never-
theless wine makes the best and most highly valued.
The very word vinegar shows you how the thing
itself is made, ^vinegar' meaning nothing more nor
less than ^sour wine' — vin aigre."

*^Why, so it does!" Claire exclaimed. ^*I hadn't
noticed it before. The two words fit together just
right; not a letter too many, and not a letter too
few."

252

VINEGAR 253

i i

In wine/' Uncle Paul resumed, '4t is the alcohol,
and the alcohol alone, that turns sour. That is to
say, you can't make good vinegar without good wine.
The more generous the wine, or, in other words, the
richer it is in alcohol, the stronger the vinegar. Peo-
ple often make a mistake on that point: they think
that poor mne, the final drippings from the wine-
press, the rinsings of bottles and casks, will in course
of time take on sufficient sourness. A great mistake.
Such watery stuff cannot possibly yield what it does
not possess. As soon as the small proportion of al-
cohol it contains has turned to vinegar, that is the
end of it; no matter how long you wait, there will
be no increase of sourness. The rule has no excep-
tions: to obtain good vinegar use good wine, wine
rich in alcohol.''

^'But you have n't told us yet," said Jules, ^'what
must be done to change the wine into vinegar."

^^That takes care of itself. Leave on the kitchen
sideboard an uncorked bottle of wine, not quite full,
and in a few days, especially in summer, the wine will
turn to vinegar. On the express condition of its be-
ing exposed to the air, wine will turn sour of itself,
and all the quicker when a warm temperature has-
tens the process of decomposition in the alcohol.
That shows you at once the care necessary for keep-
ing table wines and preventing their turning sour.
If in bottles or demijohns, they must be tightly
corked with good stoppers, since otherwise air will
get in and the wine will be in danger of souring.
As cork is always more or less porous, the top is
covered with sealing-wax when the wine is to be kept

^54 THE SECRET OF EVERYDAY THINGS

a long time; in a word, the bottles are sealed.'*

* * Then it 's just to keep out the air, ' ' said Emile,
*'that they seal the bottles with red, green, black, or
any other colored sealing-wax?''

** Merely for that reason. Without this precau-
tion air might gradually get into the bottle, and
when it was uncorked, instead of excellent old wine,
you would have nothing but vinegar. You see, if
you wish your wine to keep well, you must, above
all, guard it from the air. A partly filled demijohn
or cask, opened every day to draw out wine and then
carefully recorked, soon goes sour, especially in sum-
mer. If the wine is not likely to be all used up for
some time, the contents should be bottled and care-
fully corked. In that way the wine is in contact with
the air only one bottle at a time, as it is called for,
and so cannot turn sour provided it has been prop-
erly corked.

**Let us, then, accept it as a rule that if wine is not
to turn sour it must come in contact with the air as
little as possible. If, on the contrary, we wish to
change it into vinegar we leave it exposed to the air
in uncorked or imperfectly corked vessels. Little by
little, through the long-continued action of air, its
alpohol will turn sour. That is what happens to the
remnants of wine left in the bottom of bottles and
forgotten.

*^0f all the seasonings used with our food, vine-
gar, next to salt, is the most prized. With its cool,
tart flavor and agreeable odor it gives a relish to
dishes that without it would be too insipid. Its use
is not only a matter of taste, but also of hygiene, for

VINEGAR

^55

taken in moderation it stimulates the work of the
stomach and makes the digestion of food easier.
Combined with oil it is an indispensable seasoning
for salad. Without it this raw food would hardly
be acceptable to the stomach.''

*^That is one of my favorite dishes," Jules de-
clared, ^^ especially when it is made of spring lettuce;
the vinegar makes it taste so good, pricking the
tongue just enough and not too much. ' '

*^ Vinegar is also used in the preparation of cer-
tain well-kno^Ti condiments — capers, for example.''

**0h, how I like them!"
cried Emile, 'Hhose capers
they sometimes put into
stews. Where do they
come from?"

**I will tell you. In the
extreme south of France,
near the Mediterranean,
there is cultivated a shrub
called the caper-bush. Its
favorite haunts are rocky
slopes and the fissures in
old walls and rocks much Caper-Bush

exposed to the sun. Its branches are long and slen-
der, armed with stout thorns. These branches bend
over in a graceful green mass, and against the
darker background of foliage are set oif numerous
large and sweet-smelling pink blossoms resembling
those of the jasmine. Well, these blossoms, before
they open, are capers. As little buds they are gath-
ered every morning, one by one, and pickled in vine-

^56 THE SECRET OF EVERYDAY THINGS

gar of good quality. That is all that is done to them.
So when Emile smacks his lips over the caper sauce,
he is eating nothing more nor less than so many
flower buds.'*

''I shall like them all the better for knowing they
are flowers," the boy declared.

**In like manner gherkins are pickled in vinegar.
They grow on a vine much like the pumpkin-vine.
Similar treatment, too, is given to pimentos, some-
times called allspice on account of their spicy taste,
which becomes unbearably strong when the fruit is
ripe and coral-red. I will remind you that all pick-
ling with vinegar should be done in vessels not glazed
on the inside with lead. I have already told you that
ordinary pottery is glazed with a preparation that
contains lead. Strong vinegar might in the long run
dissolve this glaze and thus acquire harmful quali-
ties. Keep your capers, pimentos, and gherkins in
glass vessels, or at least in pots that are not glazed
inside.

*^In conclusion I will tell you that vinegar has the
property of making meat tender. To insure tender-
ness in a piece of beef it is sprinkled several days in
advance with a little vinegar to which have been
added salt, pepper, garlic, onions, and other season-
ing, according to the taste of each person. In this
mixture, however many of these ingredients there
may be, vinegar plays the chief part. This process
is called sousing the meat.'*

It is a little strange that although excellent cider is produced in
France, especially in Normandy, it seems not to be used for making
vinegar. — Transldtor's Note.

CHAPTER XL VII

THE GRIST-MILL.

THE supply of flour in the house was getting low.
Accordingly a trip to the mill was undertaken.
The donkey bore a sack of wheat across his back, and
as he made his way along with short steps the pa-
tient animal cropped here and there from the hedges
a mouthful of thistle blossoms, a rare dainty to his
palate. The children ran this way and that, picking
wild flowers or chasing butterflies, and returning
now and then to Uncle Paul with some treasure from
Mother Nature ^s store to exhibit to him.

Before long the sound of falling water and the
tick-tack of the mill, from its half -concealment amid
the foliage of willows and poplars, fell on the ear.
Ducks were returning in single file from their bath,
some of them as white as snow, with feet and beak
orange-yellow, others with head of bright green,
wings emblazoned with a splendid blue spot in the
middle, and tail surmounted by a little curled feather.
Ducklings were picking up, here and there, with
noisy demonstrations, some scattered grains of wheat
along the way. Startled by the approach of the
donkey, a flock of geese extended their necks and
uttered a raucous cry of trumpet-like resonance, to
which the donkey replied after his fashion. And so
the journey's end was reached.

257

^58 THE SECRET OF EVERYDAY THINGS

After settling certain business details with the
miller, Uncle Paul proceeded to show his young
charges over the mill and explain its working.

^^The water from the stream,'' said he, ^4s stored
up in a large reservoir by means of a dam, and is let
out by opening a sluice-gate. Through this gate it
rushes with great force and strikes against the floats
of a water-wheel set directly in its path, causing the
wheel to turn amid a shower of spray and foam, and
thus setting in motion the machinery of the mill.

i i Tjy^ grind the grain and reduce it to flour there are
two large millstones, very hard and arranged one
over the other, their flat surfaces very near together
but not touching. These surfaces are rough, the bet-
ter to seize and grind the grain between the two disks,
the lower one of which is motionless, while the upper
revolves rapidly under the impulse of the water-
wheel. Both are enclosed in a round wooden case
which keeps the flour from scattering. The upper
stone has a hole in the middle, through which, little
by little, falls the wheat contained in a sort of large
wooden funnel called the hopper. Into this the mil-
ler empties the grain-sack. As fast as it comes be-
tween the two millstones the grain is caught by the
irregularities in the surface of the revolving stone
and crushed against those in the stationary one.
The resulting powder, the coarse flour, is driven by
centrifugal force to the edges of the millstones, and
finally escapes in a continual stream through an
opening in the front of the wooden case.

^ ' But on thus issuing from between the millstones
the flour is not yet ready for making into fine white

THE GRIST-MILL 259

bread ; the bran from the husk of the grain must first
be removed. This is done by means of a sieve made
of silk, which receives the coarse meal, lets the fine
flour pass through its meshes, and retains the bran.
The mill has now done its part. To it came sacks of
wheat which, unground, could not serve as food;
from it go sacks of flour to furnish bread for daily
use. Water-power, harnessed to the machinery of
the mill, accomplishes this important transformation,
turning the millstone to grind the grain and revolv-
ing the sieve to separate the bran from the flour.
The miller's task is confined to watching the wheels
as they turn and feeding the hopper with grain.

*^What weariness and waste of time if we had not
the aid of machinery and were compelled to grind
our grain by sheer strength of arm ! You must know
that in ancient times, for lack of better knowledge,
people had to crush their wheat between two stones
after first parching it slightly over a fire. The
coarse meal thus obtained was boiled in water to a
sort of porridge and then eaten Avithout further prep-
aration, as I have explained in one of our former
talks.'' 1

''And what did they do for bread!" asked Jules.

''Such a thing as bread had never been even
dreamt of at that time. Wlieat was eaten only in
the form of porridge, a sort of thick glue, its insipid
taste somewhat relieved by parching the grain a little
to begin with, as I have already explained. Later
the plan was hit upon of making a dough of flour and
water and then baking this on the hot hearthstone,

1 See "Field, Forest, and Farm."

260 THE SECRET OF EVERYDAY THINGS

thus producing some very inferior pancakes, as thick
as your finger, stodgy and hard, and mixed with
ashes and charcoal. These were better than por-
ridge, but far inferior to the poorest bread of to-
day. By repeated trials, however, our ancestors at
last succeeded in producing bread like that on our
tables at the present time.

^^Next they had to devise means for grinding
wheat in considerable quantities, but their invention
fell far short of our modern grist-mill. A hollowed-
out stone was used as a mortar, and into this was
fitted an unwieldy pestle which was operated by a
bar pushed by wretched slaves, under the compulsion
of a cruel driver armed with a rawhide. Thus
slowly and painfully were a few handfuls of flour
produced in the time taken by one of our grist-mills
to grind a barrelful.''

CHAPTER XLVIII

BREAD

MOTHER AMBROISINE was making bread.
Standing in front of the kneading-trough, her
cheeks glowing with the exercise, her sleeves rolled
up to her elbows, alternately she thrust her closed
fists into the mass of dough, which yielded with a
dull flic-flac, then, lifting in both hands ponderous
sheets of it, she let them fall back heavily into the
trough. Marie, standing on a little stool so as to
bring herself on a level with the trough, lent what
aid she could in this rather arduous task. After
sufficient kneading the dough was cut into a number
of pieces, each of them destined to become a loaf of
bread, and these were put into little straw baskets
and covered with woolen cloths so that a gentle heat
might finish the work already begun.

Before the loaves had risen enough for baking.
Uncle Paul gathered the children around him and
told them some interesting facts about bread-making.

''If the flour were merely mixed \vith water,'' he
began, ''and the dough were then put into the oven
in that condition, the result would be nothing but a
dense, heavy loaf, a sort of hard pancake, repulsive
to the stomach on account of its indigestibility.
Bread, to be easily digested, must be full of count-
less little holes, like a sponge; it must have those

261

262 THE SECRET OF EVERYDAY THINGS

myriad eyes that help to crumble the loaf and aid
the final process of subdivision which it is the stom-
ach's part to perform. A prolonged diet of bread
made simply of flour and water is so far from ap-
petizing that it was imposed as a penance by the
Israelites in one of their sacred festivals. When
they set out from Egypt, led by Moses, they had not
time in their hasty departure to prepare bread in the
ordinary manner, and so they cooked in the ashes
cakes called unleavened bread, that is to say bread
without any leaven or yeast. In commemoration of
this event the Jews of our own day eat unleavened
bread at the celebration of their Feast of the Pass-
over. This bread consists of thin cakes, compact
and hard, of which a few mouthfuls are not unpleas-
ant, but if one eats nothing else for several days the
stomach is left unsatisfied. It is by a fermentation
similar to that of must in wine-making that flour is
made into bread, real bread, the most highly prized
of all foods and the one we never tire of.

^^ Flour contains, as I have already told you,^ first
starch and gluten, and then a small quantity of sugar
as proved by the slightly sweet taste of a pinch of
flour on the tongue. Now this tiny proportion of
sugar is precisely the substance that causes fermen-
tation in dough; that is to say, it decomposes and
forms alcohol and carbonic acid gas, as in the mak-
ing of wine."

*^ Bread and wine, then,'' said Marie, ^*are some-
thing alike in the way they are made."

**It is more than a likeness: it is a perfect same-

i See "Field, Forest, £^nd Farm,"

BREAD 263

ness so far as concerns the decomposition of sugar
into carbonic acid gas and alcohol ; and it is, finally,
a sameness in respect to fermentation. The dough
of which bread is made ferments just as does the
must that is to become wine.

**It remains for us to see how this fermentation
started. Nothing is simpler: one has only to mix
with the new dough a little of the old dough kept
over from the last bread-making and called leaven.
or rising. This old dough has the peculiarity of
making sugar ferment, of decomposing it into car-
bonic acid gas and alcohol. The noun 'rising^ comes
from the verb 'rise,' because by virtue of the rising
mixed with it the dough rises, swollen by the carbonic
acid gas that is generated.

'' Rising, as I have just said, is fermented dough
left over from the last bread-making. It is luke-
warm to the touch on account of the process of de-
composition going on within. ' '

''Grape juice gets warm, too, when it ferments,"
remarked Claire.

"Furthermore," Uncle Paul went on, "rising is
much swollen and very elastic on account of the gas
imprisoned witliin its glutinous mass; and it has a
pungent, winy odor from the alcohol formed by the
decomposition of the sugar it contains. Such, then,
is the indispensable ingredient called for, even
though in only a small quantity, in order to make
fresh dough capable of becoming bread such as we
all like so much. To please the palate, salt is also
added, but it performs no other office.

"The kneading done, w^hat comes next? I will

264 THE SECRET OF EVERYDAY THINGS

tell you. Acted upon by the rising that has been
evenly mixed with the entire mass of dough, the
sugar therein contained decomposes. The carbonic
acid gas thus generated remains imprisoned, the
gluten merely dilating under its pressure and form-
ing a spongy mass of membranous tissue packed
with innumerable tiny closed cavities. Thus the
dough rises, swells, and becomes riddled with holes
like a sponge. Baking increases this porosity, for
the gas, finding itself restrained by elastic glutinous
walls, expands still more with the heat and makes
the already existing cavities larger. To its highly
nutritive quality gluten adds another: by retaining
the carbonic acid gas within its multitudinous cavi-
ties of all sizes it makes the bread very porous, very
light, and consequently easy to digest. Hence it is
that a flour poor in gluten, such as rye meal, makes
only a compact bread, heavy for weak stomachs ; and
hence also a flour containing little or no gluten, such
as the flour made from rice, from chestnuts, from
potatoes, is totally unfit for making bread.

*^For perfect fermentation a warm temperature
is necessary. That explains why woolen coverings
are put over the little baskets of dough to keep in
the heat and ::hut out the cold. If you raise one of
these covers and put your hand on the dough you
will find it lukewarm and plump. It is warmed by
fermentation and swollen by carbonic acid gas. ' '

^^Yes, it really is warm," Claire announced, after
feeling of one of the unbaked loaves; ^^and when I
press it, it goes in like a rubber ball and then swells
out as soon as I take my hand away. ' '

BREAD 265

Toward evening the bread came out of the oven all
golden-brown on the crust, and filled the house with
a sweet smell. The children thought it tasted better
than ever, now that they knew how it was made.

CHAPTER XLIX

OTHER WHEAT PRODUCTS

ESIDES the best of bread, we are indebted to
wheat for macaroni, vermicelli, and other simi-
lar products manufactured chiefly in Italy.''

^^ Vermicelli is in the shape of long worms," ob-
served Jules.

**Yes, it is precisely from its resemblance to a mass
of long worms that it gets its name of vermicelli,
which means * little worms.' "

^^And macaroni," Marie put in, ^^ which makes
just as good a dish, seasoned with cheese, is in the
shape of long, slender tubes."

*' Besides these two," Claire hastened to add,
*Hhere are any number of other shapes — stars, cir-
cles, ovals, hearts. I have even seen the letters of
the alphabet; the first time I noticed them I was
surprised to find every one of the letters in a single
spoonful of soup. It must take a long time to cut
the dough into all those little pieces, all so beautifully
shaped."

^'No time at all, my dear," Uncle Paul assured
her. ^^In a twinkling, by means of machinery, there
is turned out any quantity of those beautiful shapes
you admire so much. Let us talk a little about how
they are made.

^*As you now know, the most nutritive part of
wheat is the gluten, which may be compared, in re-

266

OTHER WHEAT PRODUCTS 267

spect to nourishment, with meat itself. Therefore
in these Italian products wheats having the highest
percentage of gluten are used. They come from hot
countries, notably from Sicily, Africa, and Asia. In
making the dough very little water is used, in order
to get a firm dough; and to improve its taste and
color it is customary to add a little salt and saffron.
This dough is put into a metal case, the bottom of
which is pierced with a number of holes, some round,
some ring-shaped, some representing stars, some
formed like hearts, flowers, letters of the alphabet,
etc. — in fact, any shape desired. The dough is
pressed through these openings and thus made to
take the various forms I have mentioned. If the
bottom is merely pierced with small round holes, the
dough will come out of the case in long round threads
as vermicelli."

<<Why, that ^s as easy as saying good morning!'*
cried Claire.

^^If the bottom is pierced w^ith ring-shaped open-
ings, the result will be of a larger size and known
as macaroni. *'

**But I see one difficulty. Uncle Paul," objected
Marie. ^^The ,openings in the bottom cannot be per-
fect rings, for then the piece in the middle would have
nothing to hold it. "

''Very true. Accordingly the ring-like openings
are not complete, and the macaroni comes through
split all down its length. But the two edges of the
fresh dough unite as soon as the opening is passed,
stick together, and the wall of the tube is without a
break,

268 THE SECRET OF EVERYDAY THINGS

*^ Lastly, if the openings are in the shape of nar-
row slits, what comes through will take the form of
thin ribbons or thongs."

^^With openings shaped like stars,'' said Claire,
^^the dough pressed through will be in long grooved
strings ; but there won't be any stars such as we have
in soup."

^^To obtain these stars and other similar products,
there is placed, a little to one side and under the
case, a broad circular blade having a keen edge and
revolving rapidly. At very short intervals it severs
the strings of dough as they come out of their molds.
Each of these segments is a star, heart, oval, crescent,
flower, or letter, according to the shape of the orifice
that molds the string."

**Now I understand," Claire rejoined. **A big
knife goes backward and forward at the mouth of
the mold, and there falls from the bottom of the case
a shower of stars coming from the strings of dough
which the knife cuts off very short. That is the way
I get those little rounds of carrot that have such a
beautiful yellow color they remind me of gold coins.
You told us that the dough for making all these
things is colored with a little saffron. I don't know
what that is."

*^ Saffron is a plant cultivated in some of our
departments, especially around Angouleme and
Nemours. It yields a magnificent orange-yellow
color, contained in three long and slender threads
found in the very center of the flower. The flowers
are gathered as fast as they open, but only these
three thin threads are kept. The harvest is limited

OTHER WHEAT PRODUCTS

269

to this small part of the flower, so I leave you to
imagine how many blossoms it takes to furnish a
little of this coloring matter.^
These tiny threads, dried in the
sun and reduced to powder, consti-
tute the coloring-matter with which
a beautiful yellow tint is given to
dough for macaroni and similar
products, as also to cakes, butter,
and cream. Furthermore, saffron
is sometimes used, in very small
quantities, as a seasoning/'

* ^ Besides all these things you have Saffron

been telling us about,'' said Marie, 'Sve often have
groats in our soup, and groats I take to be nothing
but wheat grains without the bran."

^^ Since wheat, the richest in gluten of all the
cereals, furnishes us macaroni and vermicelli and
other similar food products, it is clear that it can
itself serve as food without being first reduced to
flour and then made into dough. We have simply
to remove its outside covering by running it between
two millstones only the thickness of a grain apart.
The two stones, not being close enough together to
crush the wheat and reduce it to flour, merely take
away the coarse outside skin, that is to say the bran.
The result of this operation is called groats, which
we may regard as a sort of natural macaroni or
vermicelli obtained at little cost with a few turns of
the mill-wheel.

1 A single ounce requires the product of more than four thousand
blossoms. — Translator.

270 THE SECRET OF EVERYDAY THINGS

^^Oats and barley also furnish groats. What is
called pearl barley is barley groats rounded under
the millstone in the form of little globules. Lastly,
semolina is groats reduced to very small grains. In
a word, it is wheat half ground and hence in parti-
cles coarser than ordinary flour. Another kind of
semolina is made of dough such as is used for ver-
micelli: the dough is chopped up into a sort of fine
sand instead of being molded in long strings. ' '

CHAPTER L

STRANGE USES OF STARCH

AFTER- explaining the important part played by
starch in plant life Uncle Paul took occasion
to name some of the less familiar sources of this
substance and to describe how it is used for pur-
poses very different from that so well known to every
housewife and every laundry-maid.

^^AU starch/' said he, ^'whether it be derived
from one plant or another, from a seed or from a
root, is readily convertible into sugar either by the
natural processes going on in vegetation or by arti-
ficial processes employed by man. The simplest ex-
pedient is the application of heat, a factor entering
into the preparation of farinaceous foods. Let me
illustrate by a few examples.

^*A potato in its raw state is uneatable. Cooked
in boiling water or roasted in the ashes it is excel-
lent. What then has happened to it? Heat has
turned a part 'Of the starch into sugar, and the tuber
has become a mass of farinaceous dough, slightly
sweetened. We can say about the same of the chest-
nut. Raw it is not good for much, though at a pinch
it can be eaten ; cooked, it deserves all the praise we
give it, and I am sure you will back me up in this as-
sertion. Here again we have a transformation of
starch to sugar by the action of heat. Beans and
peas, hard as bullets when dry, and far from pleas-

271

272 THE SECRET OF EVERYDAY THINGS

ing to the palate, are unmistakably sweetened as soon
as boiling water has worked upon their starch. Our
farinaceous foods of sundry sorts behave in similar
manner. ' '

*^Then do we make sugar,'' asked Claire, '* when-
ever we boil a pot of potatoes or chestnuts or beans?
I did n 't know we were so clever ; but I for my part
shall not put on any airs, as it isn't very hard to
make a pot boil."

*^ Man's ingenuity has devised a more effective
means than heat alone for converting starch into
sugar. The starch is boiled in water and, while it
is boiling, there is added a small quantity of a pow-
erful liquid called oil of vitriol or sulphuric acid.
This causes the starch to turn to syrup, after which
the oil of vitriol is of course removed. It has done
its office. The substance thus obtained is soft,
sticky, and nearly as sweet as honey; it is called
starch-sugar, or glucose, and is much used by con-
fectioners. As I have already told you, the sugar-
plums and other sweets that you buy at the candy
shop are in most instances the product of this in-
genious process of turning starch into sugar. And
so you see the humble potato furnishes you with
something besides the modest dish you find every
day on the table.

**But that is not the whole story. Glucose, ob-
tained as X have described, is exactly the same as the
sweet part of ripe grapes. With potatoes, water,
and a few drops of sulphuric acid there is artificially
produced, in enormous boilers, the same sweet sub-
stance that nature manufactures by the action of the

STRANGE USES OF STARCH 273

sun's rays on the full-grown grape. Now, since
grape-sugar turns to alcohol by fermenting, starch-
sugar ought to undergo a like transformation. As a
matter of fact, in northern countries, where the cli-
mate is too cold for the vine, alcoholic liquors are
made from starch that has first been changed to
sugar. Such liquors bear the generic name of po-
tato-brandy, though all seeds and roots rich in starch
may be used in the same way as the potato."

^^Let us now drop the subject of potato-brandy,
which I have briefly touched upon to satisfy your
curiosity, and return to matters of household econ-
omy. There are various starchy substances that are
much used in making soup, chief among them being
the starch of potatoes, which furnishes a nourishing
and appetizing dish of this sort and is our most im-
portant, least expensive, and most widely distributed
food product of its kind. Many of the starchy prep-
arations bearing pretentious names are really noth-
ing but this, at least in part. Other forms of the
same essential substance appear more rarely on our
tables, their higher price causing them to be reserved
for dyspeptics and convalescents. Let us consider
for a moment the chief of these.

^^In South America there is cultivated a large far-
inaceous root called manioc, which in its natural state
is a deadly poison to man, but which nevertheless
furnishes material for excellent bread. First the
root is reduced to pulp with a grater, after which the
juice is squeezed out, and with the juice goes the
poison, leaving a harmless substance rich in starch
and serving as the principal article of food for the

^74 THE SECRET OF EVERYDAY THINGS

poor in a country too hot for raising wheat. This
farinaceous substance is sold with us under the name
of tapioca. A spoonful of tapioca is transformed by
the action of boiling water into a rich jelly of ex-
quisite fineness.

^^The woods and meadows of our own latitude

abound in certain plants known
as orchids, remarkable for their
oddly shaped flowers and for
the two small tubers of the size
of pigeons' eggs in the midst of
the fine roots of the plant.
These tubers contain starch.
They are gathered in eastern
countries, and flour made from
them comes to us under the
name of salep or salop. Pre-
pared with hot water, it fur-
nishes a gummy jelly suitable
for the use of invalids.

^^ Palm-trees grow only in a hot climate. The
trunk of a palm is a graceful column, without
branches, of lofty height, tapering but little from
bottom to top, and crowned with an enormous tuft
of large leaves. One of these trees, the sago-palm,
has the heart of the trunk filled with a farinaceous
pith which is removed after the tree is cut down.
From this pith is obtained a starchy substance known
as sago and differing only slightly from potato
starch.

*' These strange forms of starch, which excite our
curiosity but are of no great use to us, must not make

Flowering Orchid

STRANGE USES OF STARCH 275

us forget the farinaceous matter furnished by our
own leguminous plants, lentils, beans, and peas.
You know the excellent thick soup we make of dried
peas, and you doubtless also know how disagreeable
are the hulls of this vegetable, tough as parchment
and without taste or nourishment.''

^^Yes," replied Emile, ''if it were not for those
horrid hulls, dried peas would n 't be at all bad. ' '

''The hulls, however, are got rid of by pouring the
soup into a colander, which retains the objectionable
part and lets through the pure pulp. But in the
process a certain quantity of nutritive matter mixed
with the hulls is lost.

"Invention and experiment have done away with
this loss. The peas are steeped a few minutes in
boiling water to burst the hulls, after which the peas
are dried in an oven and then made to pass between
two millstones sufficiently far apart to remove the
hulls without touching their contents. Thus freed of
their tough exterior, the peas are ground to powder,
which goes under the name of pea starch. In simi-
lar manner are obtained bean starch and lentil starch.
All these preparations are used for making soup, and
all have the qualities, without the defects, of the
vegetables from which they are derived ; that is, they
are freed from the disagreeable hulls that fatigue
the stomach to no purpose.''

CHAPTER LI

KICE

ONE day Emile showed a sulky face because,
when he went to Mother Ambroisine for some-
thing to eat between meals, she gave him only a slice
of bread without butter or honey or anything else on
it to make it taste good. But Marie reproved him,
saying there were plenty of people in the world that
would be glad enough to get a slice of dry bread and
would even consider it a royal feast.

* ' For it is n 't every one can have bread when he
wants it,'' she continued. *^ There are countries
where the people have never even seen such a thing.
Is n't that so. Uncle Paul?"

'*It is only too true," was his reply. *^You al-
ready know from my talks with you that not even in
our own favored land can all the people have white
bread on the table. In many homes rye and barley
serve as very inferior substitutes for wheat; and
what is true of this country is even more notably the
case throughout large sections of the world as a
whole. ' '

^ * But what do people eat if they can 't get bread of
any kind!" asked Claire.

^ ' Sometimes one thing, sometimes another. There
are a number of cereals, some of them quite unfa-
miliar to us, that afford nourishment, though fur-

276

RICE 277

nishing nothing like our light and fragrant white
bread with its crisp crust and sponge-like interior.
Asia has rice, Africa millet, and America maize, or
Indian com. In China and India the people have
hardly any food but rice cooked in water with a little
salt. In fact, half the world lives on virtually noth-
ing else.'^

^'Rice, then, takes the place of bread with those
people, doesn't it?" asked Claire.

**Yes, it may be said to take the place of our bread
when they have anything to go with it ; but not in-
frequently the whole meal consists of rice.''

^*With nothing else, at all?" asked Emile incred-
ulously.

*^With nothing else of any description," his uncle
assured him, ^ ^ from year 's end to year 's end. ' '

^ ^ Then they must be an uncommonly frugal sort of
people."

**Yes; but the warmth of the climate makes this
light diet sufficient, whereas in our latitude, with its
colder temperature, we should die of consumption if
limited to such fare."

^^Is this rice that takes the place of bread in China
and India really the same as that we buy at the gro-
cer's?" asked Claire. ^^We sometimes have that
cooked with milk."

*^ Exactly the same. It is imported into this coun-
try from distant lands. What you had last week, as
soft as sugar and as white as snow, may have come
from the country of the Hindus, or perhaps from
China. The plant producing this article of food has
a stalk not unlike that of wheat: but instead of the

278 THE SECRET OF EVERYDAY THINGS

latter 's erect ear of grain it bears a graceful tuft
of weak and drooping clusters of seeds. The leaves
are long and narrow, like ribbons, and are rough to
the touch. It is an aquatic plant, as you have
learned in one of our former talks, ^ requiring a
marshy soil and growing almost submerged in mud
and water. Artificial irrigation is often resorted to
in China to bring about the needed conditions, and
when the harvest season arrives the water is drawn
off and the reaper, sickle in hand, wades into the
mud to garner the heavily laden tops of the rice-
stalks. But it is a task far different from our cheery
harvest; there is no chirping of crickets or song of
lark to enliven the work, no display of corn-flowers
or poppies to gladden the eye. The reaper plies his
sickle with the mud and water reaching sometimes
as high as his knees.''

1 See "Field, Forest, and Farm."

CHAPTER LII

CHESTNUTS

**T HAVE explained to you what ingredients flour
X should contain to make it suitable for bread. It
must have both gluten and starch. All flours are
rich in starch, but very few possess gluten, so val-
uable for its highly nutritive qualities and its pecu-
liarity of expanding in delicate membranous tissue
when the dough ferments. You have not forgotten
that the carbonic acid gas generated by fermentation
remains imprisoned in the dough, held in confinement
by the gluten, and so causes the formation of innum-
erable empty spaces or tiny cells which should be
found in all bread worthy of the name. If gluten is
lacking, these eyes also are lacking, and the dough
makes nothing but a dense cake wholly unworthy of
the name of bread. Well, rice and maize both fur-
nish very white flour pleasing to the eye but deficient
in one essential: it has no gluten. For that reason
neither rice nor maize will make good bread, in spite
of the fine appearance of their flour.

^^ Sometimes maize is used for making what are
called corn pones, which well illustrate the ditference
between bread made of wheat and bread made of a
flour containing no gluten. These cakes have a crisp
crust that is very good to look at, but their taste does
not correspond mth their inviting appearance.

279

280 THE SECRET OF EVERYDAY THINGS

They are but coarse, indigestible eating, and after
a few mouthf uls you will be glad to desist unless you
have a very strong stomach. I class the deceptively
inviting corn pone in the same category with barley
bread, or even below it. But, as I have explained in
one of our former talks,^ maize has its uses as a
wholesome food among the farmers who raise it and
whose active outdoor life enables them to digest
coarse fare.*'

* ^ I see more clearly every day, ' ' said Claire, ^ ' that
all those foreign grains, from Asia and from Amer-
ica, are far inferior to our wheat. ' '

^^I 'd rather have a slice of bread, any time,'* de-
clared Emile, ^Hhan all the hasty pudding or por-
ridge or boiled rice you could offer me.*'

^ ^ Even without any butter on it T ' his uncle asked.

**Yes, even without butter.''

* ^ I am very glad our talks are leading you to value
bread at its true worth. If we were obliged to do
without it now that we have become used to this in-
comparable food, you may well believe it would be
the severest of privations.

**Your mention of hasty pudding reminds me of
another well-known porridge called polenta^ the na-
tional dish of Corsica and part of Italy. It is made
of chestnut flour. Let us first say a few words about
the tree that produces these delicious nuts, which
you all like so much either boiled or roasted.

*'The chestnut is a tree that lives to a great age
and attains enormous dimensions. In our mountain-
ous districts I have seen some with trunks four

1 See "Field, Forest, and Farm."

CHESTNUTS

281

Flowering Branch and Fruit
of Chestnut Tree

meters in circumference, and the trees must have
been from three to four centuries old. One of these
giants would be enough to
shade my whole garden.
The largest tree in the
world is a chestnut grow-
ing on the slopes of Mount
Etna in Sicily. It is called
the chestnut of a hundred
horses, because Jeanne,
Queen of Aragon, visiting
the volcano one day and
overtaken by a storm,
sought refuge under it wdth
her escort of a hundred
cavaliers. Under its forest of foliage both riders
and steeds found ample shelter. To encircle the
giant thirty persons with outstretched arms and
joined hands would not be enough ; the circumference
of the trunk measures in fact more than fifty meters.
In its immense size it is more like a fortress or tower
than the trunk of a tree. An opening large enough
to permit two carriages to pass abreast tunnels its
base and gives access to the cavity of the trunk,
which is arranged as a dwelling for the use of those
who come to gather the chestnuts ; for the old Colos-
sus, whose age runs into the centuries, still has young
sap and seldom fails to bear.'*

*^This prodigious tree must produce a mountain of
chestnuts,'' observed Jules.

**I imagine one year's harvest would be enough to
satisfy all of you for a long time. ' '

282 THE SECRET OF EVERYDAY THINGS

^^We should never see the last of them,'' Emile
assented, ^^for there would be sacks and sacks of
nuts — more than all the boys and girls around here
could eat in a year. ' '

Uncle Paul went on with his talk: ** Chestnuts
are enclosed in a husk bristling with long prickles
and opening at maturity in the autumn to let the
nuts fall out. There are three or four in each
husk or bur. A kind of chestnut remarkable for its
size and quality is known as the large French chest-
nut ; it comes to us chiefly from the vicinity of Lyons.
You must not confound the edible chestnut with that
of another tree called the horse-chestnut, a tree that
is often planted for ornament in parks and along
streets and public promenades. Horse-chestnuts
have all the appearance of the finest edible chest-
nuts, and are also contained in a thorny husk; but
this resemblance ends with the outside, horse-chest-
nuts being insufferably bitter in taste and abso-
lutely worthless as food.

^^ White chestnuts, or chestnuts stripped of their
shells and inner skins and dried for keeping through-
out the year, are obtained in the following manner.
On large screens extending from end to end of a long
room chestnuts are spread by the hundredweight,
and under them there is lighted a fire which produces
a great deal of smoke. As soon as they are well
dried the nuts are put into sacks, beaten with sticks,
and vigorously shaken. By this heating and shaking
the shells, which have been rendered very friable
by the heat and smoke, are broken into little pieces.
Chestnuts prepared in this way are used boiled in

CHESTNUTS 283

water, or sometimes they are ground into flour at
the mill. This flour, mixed with water and cooked
over the fire for some time, gives the porridge called
polenta.'^

^^I have never tasted polenta," said Claire, **but
I presume it is n't as good as fresh chestnuts roasted
on the stove or simply boiled. The white, dry chest-
nuts you speak of are not equal to them, either.''

**But they have the great advantage of keeping all
the year round, while fresh chestnuts spoil in a few
months."

*^When chestnuts are being roasted in the hot
ashes or on the stove, they sometimes burst mth a
loud noise and scatter the hot meat in all directions.
It 's funny to hear these little bombs, but I 'm always
afraid for my eyes. Why do chestnuts burst like
that and jump off the stove ? ' '

^^ Fresh chestnuts, like all undried fruit, contain a
little water, or moisture. The heat of the fire turns
this water into steam, which, being held captive by
the tough shell and having no outlet, keeps trying to
escape, until at last the overstrained shell breaks
and with a rush the steam bursts out with a loud re-
port through the rents, carrying with it torn frag-
ments of the chestnut. To prevent these explosions,
which waste the chestnuts by ripping them open so
violently, and are, besides, not without danger to the
eyes of those present, it is well to make an opening
for the steam so that it can get out as fast as it
forms, without gaining force by accumulating. This
is done by making an incision in the shell of the chest-
nut with the point of a knife, or by cutting away a

284 THE SECRET OF EVERYDAY THINGS

small piece of the shell. Then the steam has an
open door by which to escape, and the chestnuts no
longer burst while they are on the fire/'

CHAPTER LIII

CODFISH

EMILE came to his uncle with a question. ^ ' Tell
me," he began, ^' about the cod that has to be
put to soak several days before it is eaten, in order to
freshen it — is n't it a fish? Yet I don't see any head ;
and then it 's all flat, with the bones showing on one
side."

^ ^ Yes, ' ' was the reply, ' ^ the cod is a fish, and a very
fine one, too, as it swims in the sea. To preserve it
for keeping a long time the fishermen remove its

Cod

head, which is of little value on account of its bones ;
then they split the body all down the stomach, throw
away the entrails, and spread out the two fleshy
halves, forming together a sort of slab, broad at one
end and running to a point at the other. Finally, the
fish thus treated are liberally salted and put to dry in
the sun. So the cod reaches us all out of shape and
almost unrecognizable. In its natural state it is a
beautiful fish. The back and sides are bluish gray,
with numerous golden-red spots like those that adorn

285

^86 THE SECRET OF EVERYDAY THINGS

the trout of our fresh-water streams; the stomach
is silvery white; the upper jaw is prominent, while
from the lower hangs a worm-shaped little barbel;
and the mouth is armed with innumerable fine,
pointed teeth that fringe not only the jaws but also
the cavity of the mouth and throat as far down as
the bottom of the gullet. And so, as you might guess
from its appearance, the cod is very greedy, always
in quest of food, endowed with an insatiable ap-
petite."

*^And what does it live on," asked Emile, ^Hhis
greedy eater with teeth down to the bottom of its
gullet?"

^^It lives on other fish, weaker than itself. It is
the most formidable enemy of the small fry, which
it devours in enormous numbers. But if it is the
terror of the weak, it becomes in its turn the prey of
a host of equally greedy eaters. At certain seasons
of the year the cod gather in countless numbers and
make long journeys to lay their eggs in favorable
places. The famished denizens of the deep surround
these schools of fish; the hungry inhabitants of the
air soar over their course; the voracious occupants
of the land await them on the shore. Man hastens to
the spot to secure his share of the ocean manna. He
equips fleets and sails in quest of the fish with naval
armies in which all nations are represented; and
what he catches he dries, salts, smokes, puts into
casks, and packs in bales. Every year millions
and millions of cod perish in this way, by man's fish-
hook, by the beak of birds of prey, and by the fero-
cious jaws of rapacious fish. With such extermina-

CODFISH 287

tion constantly going on it would seem that the end of
the cod must be imminent ; and yet there is no sign
of it : the next year these fish resume their journey in
as large numbers as ever. '^

** Nevertheless,'^ said Claire, ^' their ranks must in
the end become thinner by millions and millions.''

^^ There is no sign of it, as I said before. A cod
lays nine million eggs at a time ! Where are the eat-
ers that could put an end to such a family ? ' '

^'Nine million eggs!" exclaimed Jules; ^^what a
family ! ' '

^^Just to count these eggs one by one would take
nearly a year of eight or ten working hours daily."

'^Whoever counted them must have had lots of
patience," observed Claire.

''They are not counted; they are weighed, which
is soon done ; and from the weight it is easy to esti-
mate the number when it is know^n how many eggs it
takes to make a gram."

''Ha! how easy it is when you know how!" cried
Claire. "What would have taken a year of tiresome
work becomes the affair of a minute or two."

"One of the favorite rendezvous of the schools of
cod is the neighborhood of Newfoundland, a large
island of the seas that wash the eastern coasts of
North America. Near this island is a vast extent of
shallow water called the New^foundland Banks.
Thither in summer, attracted by abundant food, come
myriads of cod from the depths of the northern seas.
Thither, also, come fishermen of all nationalities.

' ' This is not the small fishing that you sometimes
see on the banks of a river ; the fishermen do not wait

288 THE SECRET OF EVERYDAY THINGS

hour after hour under the shade of a willow for an
ill-favored little carp to come and nibble at the hook
baited with a worm, and count themselves lucky if
they go home with half a dozen diminutive fish strung
on a twig or lying in the bottom of a basket. Fish-
ing in Newfoundland is a different matter: cod are
caught by the ship-load. France alone sends out
every year four or five hundred vessels, with crews
aggregating fifteen thousand men, to the various
fisheries conducted on a large scale ; and among these
fisheries that of the cod is chief and employs the most
men. At the same time think of the Dutch, Danes,
Swedes, English, Americans, and many others, all
bound for the same fishing-grounds, their fleets
manned by an army of fishermen, and you will gain
some idea of the activity prevailing off the coast of
Newfoundland.

**At daybreak the boats leave the ship and take
their places, one here, another there, at the most
promising spots. From both sides of each boat hang
lines — stout cords of hemp carrying at the end an
iron fish-hook baited with a small fish or with a
shred from the entrails of cod taken the day before.
The voracious codfish rush up at the sight of these
dainties and greedily swallow at a gulp both hook
and bait. The fisherman pulls in his line and the
victim follows, its gullet pierced by the fish-hook.
Scarcely is the line baited again and thrown back
into the water when another cod is caught. On both
sides of the boat every man watches his lines and
keeps on renewing the bait, throwing the line into the
sea and pulling it in again with a cod at the end.

CODFISH 289

By evening the boat is filled to the gunwales with fine
large fish, still wriggling."

*' Certainly that is a kind of fishing/' said Claire,
^^that leaves no time for napping, with a line dang-
ling idly at the end of one's rod; and when you do
get a bite, it 's no miserable little gudgeon, either,
that has swallowed your hook. ' '

*'No, it is no miserable little gudgeon. The aver-
age length of a cod is one meter, and its average
weight between seven and eight kilograms. Occa-
sionally cod are taken that weigh as much as twenty
or thirty kilograms. A fish of that size caught in
one of our rivers would be the talk of all the country
around. ' '

^'You say,'' Jules interposed, ''that the hooks are
baited sometimes with small fish, sometimes even
with pieces of the entrails from the cod taken the day
before. If they pounce like that on the remains of
their own kind, codfish must be very greedy indeed !
Other animals don't devour those of their own
species."

* ' Their voracity is unequaled. With these fish the
large gobble up the small, the strong devour the
weak, without the least scruple and under no compul-
sion of extreme hunger, though they must often be
hungry enough, as they are endowed with digestive
powers that are truly astonishing. Moreover, if
some indigestible prey, too bulky for comfort and
swallowed too greedily, incommodes them, the cod
have a quick way of getting rid of it: they reject the
excess of food by vomiting. ' '

' ' Oh, the horrid creatures ! ' ' cried Marie. ' ' Their

^90 THE SECRET OF EVERYDAY THINGS

white flesh in its pretty layers does n't correspond at
all with their way of living. ' '

*^I do not deny it, but it is that particular way of
living that has given us their savory white flesh as a
highly esteemed article of food. And then this
greediness that excites your disgust is not without
its importance in the scheme of things. Think of a
cod 's family, of the nine million eggs laid by a single
fish. If all those eggs hatched and the young were
allowed to reach maturity, in a few generations the
millions would become billions, and these latter
would in turn multiply and become other billions, so
that before long there would be no room in all the
seas taken together for the codfish alone. Therefore
these fishes must eat one another now and then, if
only to offset this alarming multiplication. Man,
birds of prey, large and voracious fish — all lend a
hand in this work of extermination. And thus with
immense slaughter the prolific cod is held down to
reasonable limits within its ocean home instead of
becoming a portentous multitude.

^ ^ Filled to overflowing, the boats return in the eve-
ning to their respective ships, where the preparation
of the fish takes place. With a large knife one fisher-
man cuts off the heads ; another slits the decapitated
cods along the line of the stomach ; a third takes out
the entrails, being very careful to set aside the liver ;
a fourth flattens the fish thus treated ; and a fifth rubs
them well with salt and piles them up.'*

*^What do they do with the livers that were set
aside ! ' ' asked Claire.

CODFISH 291

**They fill a cask with the livers and leave it ex-
posed to the air. Soon decomposition sets in, the
whole mass putrefies, and there rises to the top a
greasy liquid that is known as cod-liver oil. This
oil is carefully collected, for it is held in high repute
as a medicine.''

' ^ I have heard of it, ' ' said Marie. ^ ^ They say it is
detestable to take on account of its horrid smell of
decayed fish. The way it is obtained accounts for its
nastiness. Decayed fish-livers couldn't possibly
furnish anything pleasing to taste or smell. But
after all a person conquers his repugnance if the de-
testable remedy is really a cure. ' '

CHAPTER LIV

AIR

ASS your hand rapidly before your face. Do
you not feel a breeze! Now, instead of your
hand use a good-sized piece of cardboard. The
breeze becomes stronger. Try to run while holding
an open umbrella behind you. You run with much
difficulty and seem to be dragging not a light um-
brella but a heavy load which opposes all its resist-
ance to your progress, and soon your strength is ex-
hausted.

*^ Whence comes that breeze, and what causes that
resistance? It is the air that is answerable for both,
the air in which we are all submerged like fishes in
water. Is it not true that the hand, moved rapidly
back and forth in the water, produces currents and
eddies, with little weaves that ruffle the surface and
beat against the banks! Precisely the same thing
happens when air takes the place of water. Agitated
by hand or cardboard, it is displaced, set in motion,
and made to beat in successive waves against every-
thing it encounters. Hence the pufP of air that cools
the cheek when a fan is used.

^'If you undertook to run in the water and at the
same time to drag after you a towel or even a hand-
kerchief arranged so as to form a wide-mouthed
pocket secured by the four corners, do you not think

292

AIR 293

you would experience a resistance difficult if not im-
possible to overcome ? In similar manner the fabric
of the umbrella, arrested by the air, will not let you
run fast. The more air you move, the more force
you must exert. It is all simple enough. A wide
piece of cardboard fans us much better than the hand
alone ; a large umbrella impedes our course far more
than a small one.

^*Have you ever noticed the reeds that grow in a
running brook! They are kept in constant agita-
tion. The dragon-flies or darning-needles, with
great gauze wings and long green or blue bodies, that
alight for a moment 's rest on the tips of these reeds,
have difficulty in maintaining their balance on that
unsteady perch. Why are those reeds in continual
motion ! ' '

Marie hastened to reply: ''The running water is
striking against them all the time. ' '

''Yes, that is plain. And the great trees, espe-
cially the tall poplars, that sway and bend in deep
bows and then straighten themselves up, only to re-
peat the performance — what is it that moves them
in that fashion? A giant's hand striving to uproot
them would produce no such swaying to and fro.
Obviously it is the air in motion that causes the trees
to move, just as the water in motion makes the reeds
move. Wind is air in motion, and its force is suffi-
cient to snap the poplar tree, rend branches from the
oak, and even overthrow solid walls.

"Invisible though it is, therefore, air is a very real
substance ; it is tangible matter no less than the water
of the brook, the flood of the mighty river, the billows

394i THE SECRET OF EVERYDAY THINGS

of the ocean. So long as it remains at rest we are
unconscious of it ; but let it be set in motion in great
waves, we feel it as wind and are very sensible of its
buffets. Without waiting for the next gale to con-
vince us that air is matter, we can, with a little con-
trivance, examine at close quarters this substance
that the hand cannot grasp or the eye see.

^^Let us take a drinking-glass and plunge it into
the water. It fills of itself. Now that it is full, let
us hold it in any position we wish, but without taking
it from the water. Whether its mouth be upward
or downward or sidewise, the glass will remain full.
As long as it is in the water we cannot empty it, not
even by turning it upside down. And that is just
what might have been expected ; for what disposition
could we make of its contents when there is water on
every side to take the place of any that might flow
out?

' ^ So much then being understood, what is the con-
dition of a drinking-glass as we see it standing on
the table among other preparations for dinner? Is
it really empty as we say it is before filling it with
water or wine? Does it contain nothing, absolutely
nothing? If you insist that it is empty, I shall pro-
ceed to show you that it is full, full to the very brim.
But full of what ? Full of air, nothing but air.

*^ Being immersed in air, the glass has filled itself
with air without any help from us, just as it would
fill itself with water if it were plunged to the bottom
of a well. Moreover, it remains full in any position,
even upside down; for if any of the contained air
should escape, the surrounding air would immedi-

AIR 295

ately take its place. Everything is ordered here just
as we have seen in the case of a glass immersed in
water.

^^Accordingly, when we say of a glass or of a
carafe, of a cask or a barrel, of a jug or a pitcher or
any vessel whatever, that it is empty, the current
expression used by us is not in accord with the exact
truth. The vessel designated as empty is in reality
full of air and remains full in whatever position it is
placed.

^^Eeturning now to the drinking-glass, let us
plunge it into the water, holding it in a vertical posi-
tion but with the opening downward. In vain do we
push it deeper and deeper into the liquid as far as
the arm can reach; this time the glass does not fill
with water. Being already filled with air, as has
just been explained, it cannot be filled with anything
else until that has been emptied out. The air im-
prisoned in the glass vdih no way of escape acts as
an obstacle to the entrance of the water. Under this
aspect, then, we see once more that air is real matter,
capable of resistance and not yielding its place so
long as there is no way open for it to go elsewhere.

* * Let us release the prisoner. To do this we gently
tip the glass sidewise while still holding it immersed.
A diaphanous globule shoots up through the water
and bursts on reaching the surface. Other globules
follow, and still others, as we tip the glass more and
more. They look like crystal pearls of incomparable
clearness. These transparent globules, these pearls
that make the water seem to boil, are nothing but air
escaping from the glass in little spurts or bubbles ;

296 THE SECRET OF EVERYDAY THINGS

and thus the air is rendered visible despite its ordi-
nary invisibility. We can distinguish it clearly from
the water in the midst of which it makes its ascent.
We follow its exit from the glass and note its up-
ward passage in the form of bubbles; but, once ar-
rived at the surface and mixed with the outer air, it
escapes the keenest eyesight.

^^We have just taken considerable pains to prove
the existence of a substance unseen by anybody. Is
it, then — this substance that we call air — something
of importance? Assuredly it is: air is of the very
first importance, since without it neither animal nor
plant could exist. To give you an idea of the im-
mense part it plays would require too much science
and too much time. Let us confine ourselves to a
more cursory treatment of the subject.

'^When the fire burns low on the hearth and the
glowing sticks of wood are turning dull, emitting
smoke without flame and threatening to cease burn-
ing altogether, what do we do to revive the fire?
We take the bellows and supply a blast of air. With
each putf the dull coals turn brighter, the fire regains
its vigor, and flames begin again to flicker. If gen-
erously fed with air from the bellows, the fireplace
once more resumes its radiance.

*^If, on the other hand, we wish to prevent a too
rapid consumption of fuel, we partly cover the fire-
brands with a shovelful of ashes. Under this cover,
which tends to keep out the air, the fire dies down
somewhat. Indeed, it would go out entirely if the
layer of ashes were to cover it completely and thus
wholly exclude the air.

AIR 297

*^WherL on a cold winter day we gather around the
glowing stove to warm our benumbed hands, we hear
a subdued murmuring sound that tells us the fire is
burning. We say then that the stove snores. This
sound is caused by the inrush of air through the door
of the ash-pit and its assault upon the mass of glow-
ing firebrands, the heat of which it helps to maintain.
The more air admitted, the hotter the stove becomes.
If we wish to moderate the heat, we have only to
close the door of the ash-pit. Thereupon, as air is
then admitted only in small quantities through the
joints and seams, the fire will slacken and the stove
lose its red glow and turn black. The fire would die
out entirely if no air whatever gained access to the
mass of burning fuel.

*^ These examples make suflSciently clear to us that
air is indispensable to all combustion; it revives a
dying fire ; it enters into the consumption of the fuel,
producing in the process both heat and light. With-
out air, no fire on our hearths, for wood and coal and
other fuel bum only with the help of air. Without
air, no light at night in our homes, for the illuminat-
ing flame of the lamp, of the candle, and of various
other contrivalices for dispelling darkness, goes out
as soon as the supply of air fails."

CHAPTER LV

AIR (continued)

OF all the blessings we enjoy, the first place
should be given to health, which is constantly
menaced by divers perils, and these are all the more
to be feared when they are unknown. Let us learn
what these dangers are and the means of avoiding
them; then we shall be able to preserve our health,
so far as its preservation depends upon ourselves.

*^ Prominent among the needs to which we are sub-
ject stand the need of food, the need of drink, and
the need of sleep. But there is still another before
which hunger and thirst, however violent they may
be, lose their importance; a need continually born
anew and never satisfied; a need that knows no
respite and makes itself felt whether we wake or
sleep ; by day, by night, and all the time. It is the
need of air.

' ' So necessary is air to the maintenance of life that

it has not been left to us to control our use of it as

we do in the case of food and drink. Unconsciously,

and with no volition on our part, we admit the air to

our lungs and allow it to play its wonderful part

in our system. On air, more than on anything else,

we live, our daily bread taking only second place.

The need of food is felt only at comparatively long

intervals ; the need of air is felt uninterruptedly, ever

imperious, ever inexorable.

?9a

AIR 299

*^To convince yourself of this, try for a moment to
suspend the admission of air to your lungs by closing
the doors against it, the nose and the mouth. In a
few seconds you will be forced to end the experiment ;
you will begin to stifle and will feel that death would
surely follow if you persisted in your experiment.

^'All animals, from the smallest to the largest, are
in like case with ourselves: first and foremost they
live on air. Not even do those that live in water —
the fishes and other forms of aquatic life — make any
exception to the rule : they cannot live except in
water containing a certain amount of air.

^ ^ There is a striking experiment in physics to illus-
trate this point. Some small living creature — a bird,
for example — is put under a bell-glass from which
the air is being gradually exhausted by means of an
air-pump. As the supply of air diminishes under
the action of the pump, the bird begins to totter,
struggles in an anguish painful to see, and finally
falls in the death agony. Unless air is quickly ad-
mitted once more to the bell-glass, the poor victim
will be dead and nothing can restore it to life. But
if air is admitted in time, it re-animates the bird.
Again, if a lighted taper instead of a live bird be
placed under the bell-glass, the flame is extinguished
as soon as the air is withdra^vn. The bird must have
air if it is to live ; the taper if it is to burn.

^^What I am now going to tell you will explain
briefly the reason for this necessity for air. Man
and animals have a temperature suitable to them, a
degree of warmth resulting, not from any outer cir-
cumstances, but from the vital processes within.

goo THE SECRET OF EVERYDAY THINGS

Clothing helps to retain this warmth, helps to pre-
vent its dissipation, but does not supply it. More-
over, this natural warmth is the same under a burn-
ing sun and amid the frosts of winter, in the hottest
of climates and in the coldest. Finally, it cannot be
lessened without placing us in very serious danger.
In the case of man its measurement on the centigrade
thermometer is thirty-eight degrees.

''How is it that this warmth of the body is kept
always and everywhere the same ; and whence can it
come if not from combustion? As a matter of fact
there is going on in us a continual combustion, sup-
plied with fuel in the form of food by our eating, and
furnished with the necessary oxygen from the air we
breathe. To live is to be burnt up in the strictest
sense of the word ; and to breathe is to burn. From
time immemorial there has been in use, in a figura-
tive sense, the expression, 'the torch of life.^ We
now perceive that this figurative expression is in
reality the literal expression of the truth. Air
makes the torch burn, and it also makes the animal
burn. It causes the torch to give out heat and light,
and it causes the animals to produce heat and motion.
Without air the torch becomes extinct; without air
the animal dies. In this respect the animal may be
likened to a highly perfected machine set in motion
by the heat from a furnace. The animal eats and
breathes in order to generate heat and motion, re-
ceives its fuel in the form of food, and burns it up in
its body with the aid of air supplied by breathing.

"We say that animals eat and breathe to generate
heat and motion. That is why the need of food is

AIR 301

greater in winter than in summer. The body cools
off more rapidly in contact with the cold air outside,
thus making it necessary to burn more fuel in order
to keep up the natural warmth. A cold temperature,
therefore, whets the appetite for food, while a warm
one tends to dull its edge. The famishing stomachs
of dwellers in the far North demand hearty food,
such as fat meat and bacon ; but the tribes of Sahara
are satisfied with a daily ration of a few dates and a
small portion of flour kneaded in the palm of the
hand. Anything that lessens the loss of heat lessens
also the need of food. Sleep, rest, warm clothing,
all these serve to supplement the taking of nourish-
ment and to conserve the natural heat of the body,
even in a certain sense taking the place of nourish-
ment. This truth finds expression in the common
saying that he who sleeps dines.

' ' The fuel burnt up in us by the air we breathe is
furnished by the very substance of our bodies, or
more particularly by the blood, into which the food
we digest is transformed. Of a person who applies
himself to his work with excessive ardor we say that
he burns the candle at both ends — another popular
phrase that could not be bettered in its agreement
with what is most assuredly known concerning the
vital processes. Not a movement is made by us, not
a finger is lifted, without causing a consumption of
fuel proportioned to the energy expended; and this
fuel is furnished by the blood, which itself is main-
tained by the food we eat. Walking, running, work-
ing, putting forth effort, engaging in activity of any
sort — all these do in a very real sense burn the bodily

S02 THE SECRET OF EVERYDAY THINGS

fuel just as a locomotive burns its coal in hauling
after it the heavy burden of its long train of cars.
Thus it is that exercise and hard work increase the
need of food, whereas rest and idleness diminish this
need.

^ * The coal in a furnace takes fire, becomes red-hot,
and burns up, at the same time giving out heat.
Soon there is nothing left of it but a quantity of ashes
weighing much less than the coal consumed. What
has become of the part represented by this difference
in weight? I have already told you in my talk on
combustion. It is no longer in the furnace in black
lumps visible to the eye, but it is in the air in a form
that the eye cannot see.

^^Air, as chemistry tells us, is a mixture of two
gases having very different properties the one from
the other. These gases are oxygen, an active gas
lending itself readily to combustion, and nitrogen,
an inert gas with no tendency to combustion. In one
hundred liters of this atmospheric mixture there are
twenty-one liters of oxygen to seventy-nine of nitro-
gen. Now, in burning, the carbon of coal unites with
the oxygen of the air, the two forming a gaseous com-
pound called carbonic acid gas, which becomes dif-
fused in the atmosphere. The part of the coal that
is not carbon remains in the furnace, being insoluble
in the atmosphere, and constitutes the ashes. All
the carbon, then, disappears, seeming to undergo an-
nihilation because we no longer see it, just as we
cease to see the lump of sugar dissolved in water.
This dissolution in oxygen, with the generation of
heat, is called combustion.

AIR 303

^ ' The incessant combustion going on in our bodies
at the expense of the materials furnished by the
blood is by no means comparable for violence with
the combustion taking place in a furnace. It is a
slow burning, somewhat like the spontaneous ignition
of a damp hay-mow before it bursts into flame. It
produces heat, but not enough to endanger the body
as it would be endangered by undue proximity to a
glowing furnace.

^'In passing through a furnace and maintaining
the fire therein, air changes its nature: its oxygen
unites with carbon to form carbonic acid gas, which
escapes through the chimney, while pure air is con-
tinually entering to take its place. Exactly the same
process goes on in the combustion that keeps us alive.
The lungs act as a pair of bellows, alternately filling
themselves with air and emptying themselves.
These alternating movements are known as inspira-
tion and expiration. In the first, pure air is drawn
in to burn up certain constituents of the blood and
generate heat ; in the second the air, after perform-
ing its ofiice, is expelled, not the same in substance as
when it entered, but impregnated with carbon and
unfit for breathing, like the air escaping through the
chimney from a furnace. The nitrogen in the air
undergoes no change, but carbonic acid gas takes the
place of most of the oxygen. In short, the breath
from our lungs is essentially the same as the breath
from a furnace. '^

CHAPTER LVI

IMPURE AIR

IR, on which our very existence from moment to
moment depends, exposes us to serious dan-
gers when it is vitiated with foreign emanations,
with impurities, which, though perhaps harmless
when inhaled in only a breath or two, are fraught
with peril if their admission to the lungs continues.
Breathing is never suspended, day or night, and any-
thing that disturbs it even but slightly causes un-
easiness at first and then, before long, grave danger.
We are careful to have our food clean ; we ought to
be still more careful to have our air pure, its part in
the maintenance of life being more important than
even that of food. All air injurious to health from
any cause whatsoever is called impure air.

**This impurity may be brought about in various
ways, especially by the mixture of air with other
gases, some of them dangerous merely in that they
cannot take the place of oxygen in the combustion un-
ceasingly going on in our bodies, others bringing
peril with them in the form of poisons that infect the
blood. Foremost among these latter is the carbonic
oxide, or carbon monoxide, as it is also called, which
all our devices for heating generate in greater or less
quantity, and which is therefore a serious source of
peril. This terrible gas is produced in our very
homes.

304

IMPURE AIR 305

** Carbon can burn with two different degrees of
completeness ; that is, it can combine with a single or
double portion of oxygen. Completely consumed, it
gives carbonic acid gas, the gas produced by our
breathing; half consumed it gives carbonic oxide.
Let us turn our attention to the flame of a lighted
candle. Just at the base of the flame we see a nar-
row band of beautiful blue. On the top of slowly
burning coal may be seen little tongues of flame hav-
ing the same blue color. That is the distinctive sign
of the gas we are considering; those blue flames are
produced by the complete combustion of carbon in
the formation of carbonic acid gas. But before this
final process the gas generated by the semi-combus-
tion of carbon is as invisible and subtile as the air
itself.

** Carbonic oxide is odorless, so that we remain un-
suspicious of its presence, to our great peril. In-
haled even in a very small quantity, it poisons the
blood, causing at first a violent headache with general
discomfort, then vertigo, nausea, extreme weakness,
and finally there may be a loss of consciousness.
However short the duration of this state, life is im-
perilled. In my talk on combustion I warned you
against this terrible gas, pointing out what precau-
tions should be taken in respect to heating apparatus,
the braziers used in laundry-work, and even our
modest foot-stoves. All these, unless proper provi-
sion is made for the circulation of fresh air, expose
us to serious danger. There is no need to dwell
further on this subject; I have already said enough.

*^ Carbonic acid gas, which represents the final

306 THE SECRET OF EVERYDAY THINGS

stage in the combustion of carbon, is not a poison
like carbonic oxide; our lungs always contain some
of it, since it is in every breath we exhale ; but, though
it is not a poison, it is unbreathable, being by no
means a substitute for the oxygen it has replaced in
the composition of the air. Now, carbonic acid gas is
produced in abundance all around us; in the first
place, during every moment of our lives, by our
own breathing ; secondly, by the combustion that goes
on in our heating appliances; thirdly, and less fre-
quently, by fermentation.

**I shall not here take up again the subject of our
ordinary means of heating and the dangers to our
health that lurk therein and call for vigilant precau-
tions on our part. It is a topic already sufficiently
familiar to us. Let us say a few words about mov-
able stoves.

^ ^ The ordinary stove ^ has its undeniable merits.
It is the best heating apparatus in respect to facility
of installation, economy of fuel, and conservation of
heat. But it is defective from the hygienic stand-
point, especially in a small room occupied by many
persons; it does not provide adequately for the re-
newal of the air, which it is capable of poisoning with
its carbonic oxide.

*^A form of stove that should be absolutely forbid-
den in our dwellings is the so-called American or
movable stove, which is furnished all ready to be set
up and is installed perhaps first in one room and then
in another, without proper precautions as to its

1 The European built-in stove of tile or brick is here meant. —
Translator.

IMPURE AIR 307

adaptability to the apartment to be heated. By its
mode of slow combustion it generates carbonic oxide
in great quantities, and this may escape into the room
at night and bring death to the sleepers. Too many
accidents have already demonstrated the peril lurk-
ing in this form of heater.

*^ Fermentation, or the decomposition that goes on
in the sweet juice of grapes in the process of turning
to wine, produces carbonic acid gas in abundance.
Hence it would be foolliardy unless assured before-
hand of finding adequate ventilation, to make one's
way into the vault or cellar where must is ferment-
ing ; and it would be still more foolhardy to descend
into a wine-vat even after the wine itself has been
drawn out. Carbonic acid gas may be there, form-
ing a layer or stratum of some depth, since it natu-
rally sinks to the bottom because of its being heavier
than air. Hardly has the rash adventurer entered
this layer, entirely undetected by the eye, when he
falls unconscious, as if struck by lightning. Succor
in this conjuncture is fraught with danger, and when
it arrives it is often too late.

^'The lesson is plain: the most elementary pru-
dence calls for. circumspection in entering any room
or other enclosure where carbonic acid gas from fer-
menting wine may be present. Before entering there
should always be a preliminary testing of the atmos-
phere. A lighted paper attached to the end of a long
pole should be introduced into the wine-vat and into
the remotest corners of the cellar. If the paper
burns as usual, the atmosphere is free from danger ;
if it burns dimly, smokes, or, surest sign of all, goes

308 THE SECRET OF EVERYDAY THINGS

out altogether, carbonic acid gas is certainly present.
Until ventilation has removed the danger let no one
venture where the paper refuses to burn.

** Similar precautions should be taken in the case
of recently opened crypts, deep excavations in aban-
doned quarries, and unused wells. Their atmos-
phere, often vitiated by carbonic acid gas, should
first be tested with a lighted paper.

^^ After entering the lungs air gives up a part of its
oxygen to the blood and receives in exchange an
equal volume of carbonic acid gas produced by the
combustion that takes place in the body. Hence the
breath exhaled from the lungs is less vivifying than
normal air. No argument is needed to prove that
respiration cannot continue indefinitely in an atmos-
phere not subject to renewal. The ordinary propor-
tion, twenty-one per cent, of oxygen in the air is
never completely exhausted; but any considerable
diminution, with the accompanying substitution of
carbonic acid gas, is enough to render breathing diffi-
cult and, before long, dangerous. Placed under a
bell-glass with no provision for renewing the air,
any living creature will succumb in time, its duration
depending on the rate of respiration.

^^One word more : in its passage through the lungs
the breath becomes laden with noxious emanations,
the invisible refuse of the human organism in its un-
ceasing process of destruction and reconstruction.
Man's breath is pernicious to man. Air is vitiated
by merely remaining in the lungs, where it loses a
part of its vivifying element.

^^For these various reasons it is important that

IMPURE AIR 309

strict attention be paid to the renewal of the air in
dwellings, especially in the rooms used for sleeping,
these latter being usually small and almost always
kept carefully closed for the sake of warmth and
quiet. Alcoves and bed-curtains protect us, so that
we are shut in with a limited supply of air which all
night long undergoes no renewal, whereas in the
other rooms of the house there is during the day a
constant circulation of air through the frequent open-
ing of windows and doors. When we awake in the
morning the air about us cannot but be impure. Let
us then open our bedroom windows as soon as pos-
sible and allow the pure outside air to flood the cham-
ber and replace the unwholesome atmosphere formed
during our sleep. Let us also admit the sunlight,
another powerful vivifying agent, that it may pene-
trate with sanitary effect the depths of our alcoves
and the darkness created by our drawn curtains.

^^ Under ordinary conditions air circulates about
us in such abundance that we hardly have to pay any
attention to its quantity ; but this is not so in a closed
room, a dormitory for instance, where a number of
persons pass the night. Then it becomes necessary
to provide a sufficiency of air for each one breathing
within this limited space. Now, there passes
through the lungs of every one of us about ten thou-
sand liters of air per day, or four hundred and fifty
per hour, which amounts to nearly four cubic meters
for a night of eight hours. But since air is vitiated
by respiration long before its oxygen is notably les-
sened in quantity, it is advisable to multiply this
four by ten at least and to provide forty cubic meters

310 THE SECRET OF EVERYDAY THINGS

of space for each person occupying a sleeping-cham-
ber in which the air, all night long, is not renewed.
Indeed, if double this allowance is made, the demands
of hygiene would be no more than satisfied.

<<Eggs that are no longer fresh, and in which de-
composition has begun, give out a noisome odor
known well enough as the smell of rotten eggs. They
tarnish any silverware that comes in contact with
food containing them. These two effects proceed
from the same cause, sulphureted hydrogen, a com-
pound of sulphur and hydrogen. This gas is not
only nauseating; it is also, a more serious matter,
highly poisonous, being comparable with carbonic
oxide in its harmful qualities. Whoever inhales it
quickly succumbs.

^^Now it so happens that sulphureted hydrogen is
a constant product of the decomposition taking place
in excrementitious matter, so that care is necessary
that dwellings and especially sleeping-rooms be at a
safe distance from all such sources of infection, and
that any possible danger therefrom be counteracted
by abundant ventilation.

*^Nor is sulphureted hydrogen the only injarious
product of decomposition. Everything that decays
gives forth exhalations, whether malodorous or not,
that cannot but injure our health. Therefore let us
put a safe distance between our dwelling-houses and
our stables, hen-coops, rabbit-hutches, dung-heaps,
and other similar menaces to human welfare.

**In the country there is shown a somewhat exces-
sive scorn of these dangers, but this carelessness is
usually counterbalanced by plenty of ventilation.

IMPURE AIR 311

Doors and windows imperfectly closed, badly fitting,
gaping with cracks, and often wide open, allow free
access of fresh air to every nook and comer. Never-
theless every deposit of refuse too near a well threat-
ens the health of the whole household using that
well."

i i

CHAPTEE LVII

GERMS

HEN a sunbeam penetrates the twilight of a
darkened room its course is defined by a
straight shaft in which innumerable corpuscles, ren-
dered visible by the bright illumination, are seen
whirling and eddying in constant though gentle mo-
tion. Outside of this shaft the air, though it appears
to us perfectly limpid, is laden in the same degree
with similar particles of dust. On account of their
smallness these atmospheric impurities escape detec-
tion; but let a ray of sunshine illuminate them and
turn each one into a point of light, and straightway
they become visible, at any rate the largest ones.
Others, and these form the greater number, defy the
scrutiny of the sharpest eye even in a ray of light.

' ' Now, what are these atoms, visible and invisible ?
They are made up of an inextricable mixture of a
little of everything. There are mineral particles
raised from the ground by the wind, coal-dust from
the smoke emitted by our stoves and fireplaces, tiny
shreds of wool and cotton worn away by the friction
of our clothes, minute fragments of wood from the
wainscoting, and loosened particles of paint. In
short, the pulverized product of all the wear and tear
that goes on around us is here represented.

**So far there is nothing remarkable and certainly

312

GERMS 313

nothing dangerous unless in exceptional circum-
stances, when this atmospheric dust comes from
poisonous substances. Our interest in the subject
increases when we learn that there also float in the
air, in prodigious multitudes, all sorts of germs of
animalcules, seeds of the lowest forms of vegetable
life, in most instances too small to be seen without
the aid of a good microscope.

**Let us consider the simplest case, that of mold.
Every one knows that a slice of any fruit, a melon
for example, if left exposed to the air, no sooner de-
cays than it is covered with a long silky do^^^l. This
down, composed of ramified filaments standing up
against one another, is a vegetable gro^vth belonging
to the same class as the mushroom. Its common
name is mold. Whence comes this plant, so curious
if examined closely, with its little black heads full of
spores? Is it engendered by decay?

*^That is the general belief; but let us not be de-
ceived. Decay does not engender anything ; it is not
a cause but a result. The slice of melon in decaying
does not create the mold; on the contrary, it is the
mold that induces the decay of the slice of melon, at
the expense of which it develops. This lowest form
of vegetable life has its origin in a germ, we may call
it a seed, just as an oak has its origin in an acorn.
Every living thing, animal or plant, without any ex-
ception, is derived from a previous living thing of
like sort, which has furnished the germ or seed for
the new life. Life is always the product of life,
never of decay.

^* Accordingly, the mold must have been sown.

314 THE SECRET OF EVERYDAY THINGS

But by whom or what! Evidently by the air, for air
is the only thing that has come in contact with the
slice of melon. The conclusion is obvious : there are
in the air, floating unseen amid the multitude of other
microscopic particles, the germs of mold that induce
the rotting of fruit ; they are there in immense num-
bers, for the growth of mold is very thick ; they are
everywhere, for in whatever part of the house the
slice of melon is left, it is attacked by mold; and,
finally, there are many different kinds, each one at-
tacking the vegetable or animal substance it likes
best.

^ ^ These germs come from former molds whose in-
visible and innumerable seeds were thrown into the
air by the bursting open of the ripened fruit of the
mold. Almost without weight, and wafted this way
and that by the slightest current of air, they sooner
or later fall upon some body favorable to their ger-
mination, a slice of melon or something else. The
sowing is accomplished and the plant grows.

^'Held in the air and borne hither and thither by
it are similar multitudes of germs representing or-
ganisms known as animalcules, infinite in variety,
and all too minute to be seen without the aid of a
microscope. These animalcules are called infusoria
because the simplest way to obtain them is to infuse
in water any substance, animal or vegetable. Let us
put to soak in a little water a few pinches of hay
chopped up fine, or some bits of grass, no matter
which. In a few days, especially in the heat of sum-
mer, the most curious population will be found
swarming in the liquid. A drop of this water no

GERMS 315

bigger than a pin's head shows us under the power-
ful eye of the microscope a startling spectacle. In
the ocean of this drop confined between two thin
plates of glass, there come and go, swim and plunge
and rise again by the aid of their cilia, infusoria of
many varieties, all in unceasing motion. Some are
flattened and oval in shape, somewhat resembling a
certain sea-fish, the sole; others are bristling
globules, whirling rapidly; still others, attached to
some bit of foliage by a spiral thread, present from
above the shape of a bell, the mouth of which, fringed
with cilia in rapid vibration, gives the appearance
of a wheel revolving swiftly. Then suddenly the
spiral thread tightens, the opening of the bell closes,
the cilia cease to vibrate. A tiny prey has just been
caught and the infusorium contracts to digest its
victim at leisure.

**Let us pause here in our description of these
animalcules and turn our attention to the origin of
the infusoria.

*^This aquatic population having its home in water
in which grass or other organic matter has decayed
can come only from germs brought by the air. Let
us boil a little hay in water and pour the still hot
and limpid decoction into a glass. The liquid, when
freed from the last remnants of hay, is perfectly
clear, with a slightly yellowish tinge. But, behold,
in a few days it becomes clouded, turbid. Examined
closely under a microscope, it is seen to be peopled
with infusoria. The germs of these animalcules were
not furnished by the water and hay used, for if they
contained any, which might well have been the case,

316 THE SECRET OF EVERYDAY THINGS

the act of boiling would have killed them beyond
resuscitation. Let us bear this fact well in mind, as
we shall soon find important applications of it; no
live thing, even if it be in the form of a germ, can
withstand the temperature of boiling water. Plant,
animal, eggy germ, seed, all perish in the heat re-
quired for raising water to the boiling point. Our
boiling-hot decoction, therefore, did not contain any-
thing having life. If, then, a few days after cooling
off, it is found to be teeming with life, these organ-
isms can owe their origin only to the dust of the air,
rich in infusorial germs.

^* Should any doubts remain on this point, the fol-
lowing experiment will dispel them. The infusion
is poured into a glass flask, the neck of which is then
melted and drawn out into a fine tube. The liquid
is now raised to the boiling point in the body of the
flask. Steam rises and as it escapes in a jet through
the small opening of the extended neck it drives out
all the air, after which the flask is hermetically sealed
by melting the tip of the neck. Henceforth no in-
fusoria can by any possibility make their appearance.
For years and years the decoction of hay will remain
perfectly limpid, developing not the slightest cloudi-
ness, and miscroscopic examination will prove that
the clear liquid contains nothing capable of produc-
ing life without intervention from outside. But let
the tip of the neck be broken and air enter, and very
soon the usual infusoria will appear.

^^ Below the infusoria are microbes, smaller in size,
of much simpler structure, and apparently belonging
to the vegetable kingdom. Microbes are the infi-

GERMS

317

nitely small in living form. A thousand of them
placed end to end would in most instances measure
scarcely a millimeter. There are some that are
visible only under the most pow-
erful microscope. Thus exam-
ined, they appear as bright
points, constantly trembling and
of various shapes, some oval or
rounded, others rod-shaped, and
still others bent or curved like a
comma. They are everywhere,
in numbers that defy counting;
they are in the air, the water, the
ground, in decaying matter, in the
bodies of animals, and in our o^vn
bodies. They lay claim to every-
thing.

*^What part do these infinitesi-
mal organisms play in the order
of things 1 They play a very im-
portant one. Let us give two ex-
amples.

** An animal dies. Its body de-
cays and is sooij resolved into its
primitive elements, which are seized upon for the
nourishment of growing vegetation. The putrefy-
ing flesh is converted into flower, fruit, grain, nutri-
tive matter. What agency effects this wonderful
transformation? It is the microbe, which clears
away dead matter and restores its elements to the
realm of the living. By developing and multiply-
ing they induce decay, which gives back to life's

Microbes (much
enlarged)

318 THE SECRET OF EVERYDAY THINGS

workshop materials otherwise unavailable for use.
Without their intervention the work of life would be
impossible because the work of death would be in-
complete.

^*As another instance take grape juice in the proc-
ess of fermenting and becoming wine. The liquid
heats as the result of its own internal activity; it
begins to foam, and big bubbles of carbonic acid gas
are formed, until at last there is developed that winy
flavor which succeeds to the sugary taste of the
earlier stages. This process is called fermentation.
What induces it and thus gives us wine? It is a
microbe, the same as that we find in yeast. In order
to get nourishment for itself and to multiply until its
numbers defy computation, this yeast microbe de-
composes the sugar in the grape juice, resolving it
into alcohol, which remains in the liquid, and car-
bonic acid gas, which escapes. Such is the secret of
the making of wine, beer, and other fermented drinks.

*^ Among the various tasks performed by microbes
let us henceforth remember putrefaction and fer-
mentation.

*' These two infinitely small destroyers, one of
which makes alcohol out of sugar, and the other re-
duces a dead body to dust and gas, warn us that other
microbes carrying on their work of demolition at the
expense of our own organs may by their prodigious
multitude give rise to dangerous diseases. One of
them, in fact, produces cholera, that terrible epidemic
the very name of which terrifies us ; another causes
typhoid fever, which every year claims thousands of
victims ; and still others, each according to its apti-

GERMS 319

tude, engender various ills which science is every
day making known to us in increasing numbers.
The decay of our teeth, with the extreme pain caused
by it, is due to a microbe ; the slow wasting away of a
consumptive's lungs is traced to a microbe; the big
purple carbuncle that causes so much suffering, this
too is the work of a microbe. Enough of these tor-
tures for the present. You can see that of all our
enemies the infinitely small is the most terrible.

^'Microbes are everywhere, we say, especially
where filthy conditions prevail, whether in the air or
in the water. The air in a hospital ward contains
more microbes than that outside; the air of cities,
where we live piled one on another, so to speak, has
far more than the air of the country ; the air of low
plains carries a greater number than that of the up-
lands. High mountain air has none at all. There
in truth may be found the pure atmosphere so con-
ducive to health.

*' Water is even richer than air in microbes, espe-
cially when it is defiled with sewage. It is estimated
that such water may contain various kinds of
microbes and their germs to the frightful number of
one hundred million per liter. Not all of these, it is
safe to say, are harmful; far from it; but in so im-
mense a multitude there must certainly be some bad
ones.''

CHAPTER LVIII

THE ATMOSPHERE

S we have seen, all animal and vegetable life
lias need of air, and air is supplied in inex-
haustible volume. It forms around the earth a con-
tinuous envelop known as the atmosphere and having
a thickness of at least fifteen leagues.

**It is a veritable ocean of air, but an ocean with-
out shores, an ocean holding in its lowest depths all
that lives and moves upon this earth of ours. In its
upper reaches it extends far beyond the loftiest
mountain peaks and occupies regions of space that no
bird in its most daring flight has ever visited ; and it
makes its bed upon the dry land of the continents
and upon the waters that encircle them, these latter
constituting another ocean far heavier and denser,
the abode of the aquatic population of the globe.

*^In the daytime we see above our heads a bound-
less blue vault which we call the sky ; but this vault
is one in appearance only, owing its seeming exist-
ence to the atmosphere. To account for the azure
cupola of the sky, note that substances very slightly
tinged with color do not show this color until they
are seen in masses of great thickness. A pane of
glass looks colorless, yet if viewed edgewise it is
found to be of a delicate green hue. In the first posi-
tion there is nothing in the thin pane to arrest the

320

THE ATMOSPHERE 321

eye ; in the second, the considerable body of glass pre-
sented reveals the green color.

** Similarly, the water in a bottle, being of small
volume, appears colorless ; but if we look at a great
mass of water, such as a lake or the ocean, it is seen
to be tinged with either green or blue. The same
holds true of air: colorless and therefore invisible
where a volume of only moderate thickness is con-
cerned, it becomes visible and shows its delicate tint
of blue if the thickness be considerably increased.
Thus it is that the enormously thick layer surround-
ing the earth assumes the appearance of an azure
vault.

* * Since it is matter, air must have weight ; and in
fact it has — very slight weight, it is true, but more
than that of many other substances. Suppose we
had a hollow cube measuring one meter each way.
The air contained in this cube would weigh one kilo-
meter and three hundred grams. A like volume of
water weighs one thousand kilograms, or seven hun-
dred and sixty-nine times as much.

^^It is in the atmosphere, now higher, now lower,
that the clouds float ; and it is in the atmosphere that
smoke rises and is dissipated. Why do clouds re-
main at a considerable height, and why does smoke
rise ? Because they are lighter than air. A piece of
wood, if forced down to the bottom of a body of water
and then released, immediately comes up again of its
own accord; it does so because it is lighter than
water. Exactly similar is the behavior of clouds and
smoke, which are lighter than air, in the atmospheric
ocean in which they are immersed. If there were no

32a THE SECRET OF EVERYDAY THINGS

atmosphere, smoke would not leave the ground and
clouds would trail along the surface of the earth.
If there were no atmosphere to offer resistance to the
strokes of their wings, birds could not fly.

^^To protect us from the cold we have clothing.
The terrestrial globe likewise has its thick blanket
under which is preserved for some time the heat re-
ceived from the sun during the day ; it has its atmos-
phere, a cloak of air fifteen leagues thick. Without
this protection, which plays a part similar to that of
our eider-down bed-coverings in retaining heat, the
earth would undergo, every night, a cooling-off that
no living creature could withstand.

^^With any diminution in the thickness of this en-
velop of air there is a corresponding decrease in the
protection it furnishes, just as is the case in respect
to the clothes we wear. Hence it is found that the
cold increases rapidly in the upper regions of the
atmosphere, because the protecting covering is thin-
ner in proportion to the depth of atmosphere below.
Thus we understand why very high mountains are
covered with snow the year around, not even except-
ing summer: their summits, less protected by the
atmospheric blanket than the surrounding plains, are
subjected to a more rigorous cooling-off at night.

^^ A considerable mass of cotton may be compressed
in the hands until it becomes a small ball. In like
manner air is compressible: it becomes denser and
occupies less space in proportion to the pressure
exerted upon it. With this truth in mind let us con-
sider the atmospheric envelop in its entire thickness.
The layer next to the ground bears the weight of all

THE ATMOSPHERE 323

that is above ; it sustains the greatest pressure and
therefore, volume for volume, is the richest in matter,
just as the most compact ball of cotton is the one con-
taining the most of that material. Without entering
into further details we see that the atmosphere be-
comes less and less dense as we ascend, because it has
less and less of superincumbent atmosphere to sup-
port.

** Living at the bottom of this atmospheric ocean,
we breathe its lower layers, the air of which, denser
than elsewhere, meets the needs of our lungs. If we
ascend three or four thousand meters we find the
air thinner and respiration difficult and inadequate.
Higher still, we experience something worse than
discomfort; we face very serious danger. Finally,
at a height not really tremendous in itself strength
fails, the mind wanders, and sudden faintness super-
venes, followed by death.

^^ Though ]ife ceases for lack of sufficient air, the
atmosphere is still there, its upper layers extending
far beyond the elevation here referred to ; neverthe-
less it has not the degree of density required for sus-
taining life. Only in the lower layers of the atmos-
phere, then, is the air suitable for breathing; at a
greater height all life ceases. Of course no bird
mounts to those desert spaces; nor, in fact, would
its wings find there a sufficiently resistant atmos-
phere to admit of flying.

*^ Freezing cold, prostrating physical discomfort,
and at last sudden death — these await the daring ad-
venturer who attempts to scale the vault of heaven.
Let us then stay below, in the lowest depths of the

SU THE SECRET OF EVERYDAY THINGS

atmosphere, the only abode suited to our needs ; and
if we are seized with a desire to know more in detail
what goes on up yonder, let us be content to hear
the report of those audacious explorers who have
penetrated the upper regions of the atmosphere.

^^A balloon ascends to heights unattained by the
loftiest mountain peaks. The enormous globe of
woven fabric is inflated with a gas called hydrogen,
like ordinary air in its invisibility, but far rarer and
lighter, weighing only a hundred grams to the cubic
meter, or one thirteenth as much as air. Thus ren-
dered buoyant by this tenuous gas, the balloon
ascends because its total weight is less than that of
a like volume of atmospheric air.

*^It carries heavy weights, very heavy weights, it
is true, notably the aeronaut, the one who makes the
aerial voyage ; but it rises in spite of this. How is
it to be explained! It is very simple. Recall once
more the piece of wood forced to the bottom of a body
of water and rising of its own accord as soon as
released. A piece of lead would not have acted thus,
because lead is heavier than water ; but with outside
help it will rise readily enough. Attach to it a piece
of wood or, better, of cork, making sure that the piece
is large enough, and the whole will return to the
surface after being forced down into the water and
then released. The wood or cork, being lighter than
lead, will pull up the latter with it as it rises.
Exactly so does the balloon conduct itself: the very
light gas inflating it carries aloft, as it ascends, the
heavy objects in the car or great wicker basket sus-
pended from the gas-bag.

THE ATMOSPHERE 325

*^ When he wishes to come down again the aeronaut
opens a valve by pulling a cord hanging within reach
of his hand. A little hydrogen escapes and ordinary
air takes its place, whereupon the balloon, rendered
so much the heavier, begins to descend, slowly or
rapidly according to the amount of gas discharged.
With this explanation of the principles governing
the balloon's ascent and descent let us turn to the
narrative of an English scientist, James Glaisher,
who in September of the year 1862 attained the
greatest elevation yet reached by man.

''' ^We left the earth,' he says, ^at one o'clock in
the afternoon, in a mild temperature. Ten minutes
later we were floating in a dense cloud which
shrouded us in impenetrable gloom. ALfter passing
out of this layer of fog the balloon rose to a region
flooded with light, the brilliant sunshine giving to
the sky an extraordinarily vivid tint of blue.

'^ 'Above our heads we had nothing but the azure
of the firmament; under our feet lay a widely ex-
tended surface of clouds arranged in imitation of
hills, mountain chains, and isolated peaks, all of re-
splendent whiteness. One might have mistaken it
for a mountain scene covered with snow of incom-
parable purity. As we ascended we caught momen-
tary glimpses of the earth through occasional open-
ings in the clouds.

'* 'In twenty -five minutes the balloon had carried
us up four thousand, eight hundred meters, which is
very nearly the height of Mont Blanc, the loftiest
mountain peak of Europe. A like ascent on foot
would have cost us several days of extremely weari-

326 THE SECRET OF EVERYDAY THINGS

some climbing. The temperature had by this time
fallen very low, and ice was forming on the balloon.
Another upward spurt raised us to the height of
eight thousand meters, where the severest of winter
cold prevails ; and still we continued to ascend.

** 'When we had reached an altitude of eleven thou-
sand meters, or almost a league beyond the highest
mountain in the world, my assistant, Coxwell, noticed
that the valve cord was entangled in the rigging of
the balloon, and he climbed up to disengage it.

*' 'Just then my right arm became suddenly para-
lyzed. I tried to use my left, but it too was para-
lyzed. They both refused to obey my will. I then
attempted to move my body, but with so little suc-
cess that I seemed to have no longer any body at all.
I essayed at least to read the marks on the instru-
ments, but my head fell over, inert, on my shoulder.

' ' ' I had my back against the edge of the car, and
in this position I looked up at Coxwell, who was en-
gaged in disentangling the valve cord. I tried to
speak to him, but could not utter a sound. Finally
thick darkness came over me, my eyesight having in
its turn become paralyzed. Nevertheless I was still
perfectly conscious. I thought I needed air and that
I should die unless we could very soon manage to de-
scend. With that I lost consciousness just as if I had
suddenly fallen asleep. ' ^

''A minute more of this swooning fit and it would
have been all over with Glaisher. Coxwell climbed

1 The paragraphs ostensibly quoted from Glaisher's narrative are in
reality a very free paraphase, much abridged. For the author's full
account see his "Travels in the Air," Part I. Chapter 3. — Translator.

THE ATMOSPHERE 327

up into the cordage amid long icicles hanging from
the balloon. He hardly had time to free the valve
cord : the extreme cold had seized him and his hands,
benumbed and blue, refused to do their office. He
had to descend into the basket by clinging to the
ropes with his elbows.

^^ Seeing Glaisher lying motionless on his back Cox-
well at first thought his companion was resting, and
he spoke to him, but received no reply. The pros-
trate man's silence indicated that he had fainted.
Coxwell then undertook to succor him, but paralysis
and insensibility were fast overcoming the assistant
also and he could not drag himself to the dying man's
side, whereupon he at last became convinced that
they must descend without delay if they were not
both to perish in a very few minutes.

^'Fortunately the valve cord hung within his
reach; but being unable to grasp it with his hands,
benumbed as they were with cold, he seized it be-
tween his teeth and after a few tugs succeeded in
opening the valve. Immediately the balloon began
to descend. Before long, in an atmosphere less cold
and less rarefied, Glaisher recovered consciousness
and gave his attention to the frozen hands of his
companion.

''They regained the earth safe and sound, both
men, but with no desire for further ascents of a like
perilous nature. Far more serious was the issue in
the case of three French aeronauts who, some years
later, wishing to add to our knowledge of atmos-
pheric conditions, made an equally daring ascent.
When their balloon came down again two of the rash

328 THE SECRET OF EVERYDAY THINGS

explorers were dead, stiffened by the cold and suf-
focated by the insufficiency of the upper air, while the
third, saved as by a miracle, was at his last gasp.
Knowledge is sometimes bought very dearly. Sci-
ence has its heroes and martyrs.''

CHAPTER LIX

EVAPORATION

MOTHER AMBROISINE had just been wash-
ing some handkerchiefs. After soaping them
she rinsed them in clear water, and then wrung them
out as dry as she could by energetic twisting and
squeezing. That done, were they dry enough, and
could they be used just as they were !

This question Uncle Paul put to the children,
and they all agreed that the handkerchiefs w^ere still
very wet, that in fact they held an amount of water
exceeding their own weight. What, then, was to be
done in order to make them as dry as linen must be
before it can be used!

*^You all know,'' resumed Uncle Paul, ^'what
Mother Ambroisine w^ill do to the handkerchiefs:
she will hang them on a line in the sun and -in a
light current of air, if possible. If conditions are
favorable, if the sun is warm and a gentle breeze is
blowing, the handkerchiefs will soon dry. Then they
will only have to be ironed and put away in one of
the bureau drawers.

^'If the sun does not shine and it is cold, with no
air stirring, the drying will take longer. But finally,
sooner or later, the handkerchiefs will all get dry;
they will lose the water they soaked up at the be-
ginning.

329

830 THE SECRET OF EVERYDAY THINGS

* ^ Let us take another example. We will set a plate
of water in the sun. In summer, when it is warm
and clear, the water will all disappear between morn-
ing and evening, and the bottom of the plate will
be found quite dry. In winter wait a few days, a few
weeks perhaps, according to the weather, and the
same result will be attained: the plate will, in the
end, become quite empty although not a single drop
has escaped by leaking.

^^But is it necessary, after all, to have recourse
to any such experiments as these? Will it not suf-
fice to recall to mind what each one of us has wit-
nessed over and over again? Who does not know
the little puddles of water, the stagnant pools, that
collect in ruts and hollows whenever there is a fall
of rain?

^^You go by when the pool is full. Ducks are
dabbling in it and frogs croaking; black tadpoles,
toads-that-are-to-be, sun themselves on the banks,
their backs exposed to the noonday warmth, their
bellies in the tepid mud. Strange plants, confervce,
as they are called, display their long tufts of sticky
green filaments.

* ' You go by again a little later and no more ducks
are dabbling, no more frogs croaking, no more tad-
poles frisking, no more confervce showing their ver-
dure. All have vanished. The pool is dry. Doubt-
less the soil has drunk up, little by little, at least a
part of the stagnant sheet of water where the toad ^s
black family was disporting itself and where the little
ducks came waddling in single file to take their first
lessons in swimming ; but in many cases this slow in-

EVAPORATION 331

filtration of the water into the ground cannot ac-
count for the pool's disappearance.

^^It may be that the bottom of the natural basin
in which the rain-water has collected is formed of
compact earth — of clay, for example, which is abso-
lutely impervious to water — or it may be the bottom
is of solid rock which, by its very nature, allows not
the slightest infiltration.

^^How, then, has the pool disappeared? What has
become of the water it contained, if the earth has not
drunk it up? There were, perhaps, thousands of
liters, and now it is all gone. A thirsty chaffinch
would not find enough water there to wet its throat.
What, too, became of the plateful of water set in the
sun, and the moisture in the linen washed by Mother
Ambroisine?

^^To find the answer to this question, which will
lead us farther than you think, it is enough to recall
what happens when a pot full of water is put on the
fire. The liquid first gets warm and then begins to
boil, while from the pot there burst turbulent jets of
what looks like white smoke, hot and damp, and
known to every one as steam.

**Now, this white smoke, this steam, is water, noth-
ing but water ; yet water under another form, water
that, instead of running or dripping, expands in the
air, floating there as light and thin as the air itself,
and becomes dissipated until not a particle of it is
visible.

** Watch a puff of steam coming out of the pot.
You can see plainly enough the jet of white vapor
at the mouth of the vessel, but a little higher up you

33a THE SECRET OF EVERYDAY THINGS

see nothing whatever, the white puff having become
dissipated in the air and being henceforth lost to
sight. We no longer see the steam; nevertheless it
still exists, whether it has been dispersed through the
room, whence it will escape by the doors and win-
dows, or has been carried up the chimney by the cur-
rent of air ascending from the fireplace.

^ ' Thus the pot loses its contents through its mouth ;
little by little it empties itself from above ; it yields
its water to the atmosphere under the form of vapor.
The hotter the fire the more rapid the loss. Always
losing in this way and receiving nothing, the pot must
sooner or later become dry. If the cook does not
watch it and, before it is too late, replace the water
that has boiled away, the vegetables she has put in
it to cook will burn.

^^What are we to conclude from this instance of
the pot of water on the fire? This : the heat reduces
water to vapor or, in other words, to something as
thin and invisible as air itself. I insist on this
word invisible because — note this well — the white
smoke we distinctly see rising from the pot is not yet
real vapor.

^^Let us call it, if you like, imperfect vapor, or
visible vapor, or mist. But when the white smoke
has been dissipated in the air and become so thin
and limpid that the eye can no longer detect it, then
it is real vapor.

**What the intense heat of the fire accomplishes
in a short time the sun also effects, but more slowly.
It is the sun's heat, then, that dries up the pool by
changing its water into vapor; it is the sun's heat

EVAPORATION 333

that dries the plate by reducing its contents to vapor ;
it is the sun^s heat that dries the linen hung on the
line by converting the moisture it holds into vapor.

^' Vapor from the pool, from the plate, from the
linen, from the boiling pot, all goes into the air and
floats there invisible, driven hither and thither by
the least puff of wind. The greater the heat, the
more rapid the transformation of water into vapor,
and also the greater the air's capacity for receiving
this charge of invisible moisture.

^^That is v/hy the duck-pond dries up sooner in
summer than in mnter, and why the linen that dries
so quickly on a hot day is very slow in drying on a
cold and dull one.

^*But, whatever the temperature, air cannot re-
ceive an unlimited quantity of vapor. When it has a
certain amount it becomes too damp to absorb a fresh
supply of moisture.

*^A perfectly dry sponge readily drinks up a cer-
tain quantity of water; already wet, it can take up
only a smaller quantity; and if entirely saturated,
it will take up none at all. A pile of dry sand, with
its base resting in water, gradually becomes damp
to the very top, and when it is thus wet through it
cannot absorb any more water.

**Air behaves in the same manner: in a dr}^ state
it readily absorbs vapor; saturated to a certain
point, it will receive no more. It is a soaked sponge
in its powerlessness to drink up more water. So
you can easily understand w^hy air in motion, that
is to say wind, accelerates the drying of linen and
the disappearance of the water in a pond.

334 THE SECRET OF EVERYDAY THINGS

^'The more humid the air, the less rapidly will it
receive vapor, the formation of which is thus ar-
rested ; but if the air in contact with the pond, or with
wet linen, or with any sheet of water, be constantly
renewed by a breeze, the damp air is succeeded by
dry, which in its turn becomes charged with vapor
and gives place to other air, and this also carries on
the drying process. Thus the transformation of
water into vapor proceeds uninterruptedly.

**Let us sum up what we have just learned. Heat
changes water into vapor, that is to say into some-
thing light and thin, which floats in the air and
becomes dissipated until it is as invisible as the air
itself. This change is called evaporation. Water
evaporates at any temperature, but the more rapidly
the greater the heat.'*

CHAPTER LX

HUMIDITY IX THE ATMOSPHERE

*' A FTER a good rain the fields are muddy; thou-
jLjl sands and thousands of threads of water run-
ning down the slopes have filled the ditohes or col-
lected in puddles and pools ; the foliage of the trees
shows a glossy green and shines as if the watery
coating left by the storm were so much varnish; at
the end of each leaf, at the tip of the tiniest blade
of grass, trembles a drop of water, flashing like a
diamond in the sunlight.

**But wait a few days and if the sun is hot and the
wind blows a little, there will not be left a trace of
this shower that gladdened the farmer's heart. The
earth will have become dusty again, in the woods
the little cushions of moss that but lately were so
exquisitely fresh will have shriveled up and faded,
the leaves of the trees will hang limp and lifeless,
the puddles will be dry, and the mud will have turned
to dust.

'^^Miat has become of the quantities of water dis-
charged by the storm? The soil drank part of it,
that is certain, to the benefit of the growing vegeta-
tion; but the air — insatiable toper! — also took its
share, and a large one. The water that fell in the
form of rain from the upper air has by evaporation
returned to the atmosphere whence it came ; the air

335

336 THE SECRET OF EVERYDAY THINGS

has taken back what it gave to the soil for a little
while. The drops that sparkled at the ends of the
leaves have returned, invisible, to the immensities of
the atmosphere without touching the earth. In
short, evaporation has dissipated the waters of the
storm into space.

^^ Countless bodies of water, running or stationary,
are constantly giving oif moisture from their sur-
face by evaporation. Little brooks hastening to
unite and form a rivulet, rivulets contributing their
waters to make a river, rivers emptying into larger
rivers, and these in turn discharging their floods into
the sea; lakes, ponds, marshes, stagnant pools — all,
absolutely all, even to the smallest puddle no larger
than the hollow of one^s hand, yield vapor to the
atmosphere without a moment's pause.

*^To picture to oneself the total volume of water
thus rising continually into the air would be beyond
the power of the imagination ; and yet that is a mere
nothing, for we are forgetting the chief source of
atmospheric humidity. We forget the sea, the im-
mense sea, covering three quarters of the earth's
surface — the prodigious sea, in comparison with
which all the rivers combined are as a mere trifle.
What is a drop of water compared with a mill-pond ?
Nothing. It is the same with the waters irrigating
the continents when we contrast their combined vol-
ume with the vastness of the sea.

**From the oceans and the bodies of water on the
various continents there rises unceasingly into the
atmosphere an inconceivable quantity of vapor.
Now, this does not stay long over the bodies of water

HUMIDITY IN THE ATMOSPHERE 337

that gave it forth; the wind carries it away, to-day
in one direction, to-morrow in another, sometimes
to immense distances, so that a layer of air saturated
with moisture a thousand leagues from here may
reach us and furnish the air we breathe.

*^ Through the agency of storms, hurricanes, and
all kinds of winds, gentle or boisterous, that agitate
the air, there is brought about an indiscriminate re-
distribution, in every direction, of the vapor that
rose from any given part of sea or land. In this
way the air about us holds moisture, always and
everywhere.

**Yes, this air that surrounds us now, this air in
which we come and go, contains water in the form
of invisible vapor; and it always contains it, some-
times more, sometimes less, every moment and in all
seasons. You will be convinced of this if I succeed
in making visible to you what is now invisible; if,
in short, I succeed in reconverting into water, run-
ning water, this vapor which no eye can see.

^^As it required only a slight rise in temperature
to convert ordinary water into invisible vapor, it
will suffice to lower the temperature a little, and thus
cool the vapor, to restore it to its former condition,
or in other words to reconvert it into water. This
cooling process, this taking away of heat, will undo
what warming or the application of heat had done in
the first place. That is all plain enough, it seems
tome.

*'Let us go back a moment to the pot of boiling
water. Cover it with the lid, first wiping the latter
perfectly dry inside ; or, better still, hold the lid over

338 THE SECRET OF EVERYDAY THINGS

the steam escaping from the pot, and at a short dis-
tance from the mouth.

^^You foresee what will happen. The inside of the
lid, perfectly dry at first, will in a few moments be
covered with drops of water. Wliere do these drops
come from if not from the steam which, by contact
with the cold lid, has lost its heat, to which it owed
its subtile form, and has returned to its original
state, that of water ? So much, then, we have demon-
strated, that cold changes vapor to water; which is
exactly the opposite of the change wrought by heat.

*^For the sake of brevity we will in our future
talks use a few terms which I will here define. The
return of vapor to the state of water is called con-
densation. The opposite term is evaporation, which
designates the conversion of water into vapor. If
we wish to say that vapor becomes water again, we
say it condenses.

* * How shall we make the invisible vapor that is in
the air manifest itself as water? Nothing easier, if
we have some ice or snow at our disposal. We fill
a water-bottle with small pieces of ice, wipe the out-
side well to remove any moisture that may already
be there, and put the bottle on a perfectly dry plate.

*^We do not have to wait long for the result. The
glass of the water-bottle, at first perfectly clear, be-
comes dull and veiled in a kind of fog. Then little
drops form, grow bigger, and slowly run down into
the plate. Wait a quarter of an hour and we shall
have enough water in the plate to pour into a glass
and drink if we wish.

''Where does this water come from, if you please?

HUMIDITY IN THE ATMOSPHERE 339

Certainly not from the inside of the water-bottle, for
water cannot pass through glass. Then it must come
from the surrounding air, which by contact with the
ice-cooled glass has itself become so chilled as to
make its vaporous contents first appear as a kind of
fog, the initial step in condensation, and then run
down the glass in the form of drops. In this manner
it may be proved at any season of the year that there
is a certain amount of moisture in the air.

**We do not always have ice or snow at our dis-
posal, especially in summer. During that season
must we, then, forego this interesting and instructive
experiment 1 Certainly not. We merely have to fill
the water-bottle with very cold water and we shall
see the glass become dull and clouded with moisture.

^^ There may even be some formation of drops
large enough to run down the sides. The result will
be the same as when ice is used, only less pronounced,
because the cooling effect of cold water is less than
that of ice.

**This phenomenon may have been presented to
our view many times without attracting our notice.
The carafe of cold water placed on our table at din-
ner very soon I'oses its transparency and turns dull
from the condensation of vapor on the outside. A
glass filled with cold water ceases to be transparent,
becomes covered with a dull cloud, and looks as if
badly washed. That, too, is the vapor from the sur-
rounding air condensing — and collecting on the cold
object.''

CHAPTER LXI

RAIN

<*T^7HAT is needed to make the half -condensed

V V vapor of clouds finish condensing and turn to

water, falling in drops of rain? Very little : a slight

cooling, a breath of cold air from some less heated

region.

^^As soon as it is cooled the fine aqueous dust of
the clouds, similar to what we see rolling up in the
form of fog, collects in very small drops which fall
of their own weight.

"In passing through the dense mist below them
these droplets condense on their surface a little of
the vapor they meet with, so that they increase in
size and become drops capable of growing still
larger, until the very moment of their leaving the
clouds. Finally they fall to the ground after at-
taining a size proportioned to the thickness of the
cloud-layer through which they have passed.

* ' That is rain — one day a fine shower which hardly
bends the blades of grass, another day a heavy do^vn-
pour in big drops that patter on the foliage and
the tiled roofs. That, I say, is rain which we all so
eagerly desire when the country is suffering from
drought.

**It rains beneath the clouds that are converted
into water by being chilled ; but elsewhere it does not

340

RAIN 341

rain, the sky is blue, and the sun shines. One can
often see this uneven distribution of a rainfall. Has
it not happened to you that, with the sky all blue
overhead, you have seen in the distance something
like a vast grayish curtain, vertically striped and
reaching from the sky to the earth? That is a cloud
turning into rain and pouring out its contents wher-
ever it passes. It may even have reached you,
driven in your direction by the wind. Then the blue
sky has suddenly become somber, and you are caught
in a shower.

** Clouds may be likened to immense celestial wa-
tering-pots that travel almost everywhere at the
caprice of the winds that drive them. Every region
they visit receives a shower ; but any other, however
near it may be, receives nothing so long as it does
not lie under them. A rainfall may be local in ex-
tent and its limits so sharply defined that a few steps
in one direction will expose you to a shower and a
few steps in the other place you where not a drop
falls. But local rains are not the only ones. There
are some — and they often occur — that embrace enor-
mous regions, several provinces at a time.

*^ While the rain is falling, as we may imagine it
to fall, let us consider for a moment the marvelous
journey accomplished by a single raindrop. Whence
does it come? From the clouds floating there above
our heads, perhaps one or two thousand meters high.
It was up there when the thunder burst ; it was pres-
ent at the blinding flash of the lightning. But no
sooner was it formed than, by the force of its own
weight, it fell with dizzy speed from its lofty posi-

342 THE SECRET OF EVERYDAY THINGS

tion. Behold it rebounding from a leaf and falling
to the ground, where it soaks into the soil and adds
to the moisture essential to the life of every plant.
A head of lettuce, perhaps, in drinking it, will gain
renewed vigor.

**It came from the clouds, and clouds are made of
vapor held in the atmosphere. This in turn results
from the evaporation of water, chiefly the water of
the sea, by the heat of the sun. But of what sea?
Who can say? Who could indicate precisely from
what point of the broad ocean's surface the sun
drew the vapor that was one day to form that drop ?
Was it from the blue waves of the Mediterranean,
the smiling sea to the south of France? It is pos-
sible, if the cloud from which it fell was driven so
far by the south wind. Or was it from the greenish
waves of the ocean whose billows dash furiously
against the cliffs of Normandy and the reefs of Brit-
tany? Possibly, if the west wind drove hither the
cloud that was to let it fall.

^^It is possible, again, that the raindrop came from
a far greater distance, perhaps from some gulf
fringed with cocoanut-trees whereon perch green
parrots with red tails; perhaps from some arm of
the sea where the whale suckles its young; perhaps
from the other end of the world. Yes, there are all
these possibilities ; and then what a journey to come
to us and water a head of lettuce !

**This prodigious journey ended, in our drop of
rain at last to find rest in the plant it has watered?
By no means. Nothing remains at rest in this
world, not even a drop of water. Everything is in

RAIN 348

motion, everything is busy, everything is forever
beginning again the task already accomplished.

*^The drop of water rises with the sap from the
roots of the plant, ascends through the stalk, and
reaches the leaves, where it evaporates. The heat
of the sun reduces to vapor what it had for a mo-
ment relinquished to the earth as water. And so we
have again the drop of water high in the heavens
and transformed to an invisible state — once more
given over to the caprices of wind and storm, which
will carry it no one knows whither. One day or an-
other it will become rain again, and there is no rea-
son why it should not, sooner or later, water the
cocoanut-tree from the neighborhood of which we
supposed it to start.

*' These journeys being repeated unceasingly,
sometimes in one direction, sometimes in another,
the raindrop cannot fail some day to rejoin the sea
whence it originally came. All rain comes ulti-
mately from the sea, and to the sea all rain finally
returns.^'

CHAPTER LXII

SNOW

NOW has the same origin as rain : it comes from
vapor in the atmosphere, especially from vapor
rising from the surface of the sea. When a sudden
cooling-off takes place in clouds at a high elevation,
the condensation of vapor is immediately followed
by freezing, which turns water into ice.

**I have already told you ^ that cirrus clouds,

Snow Crystals

which are the highest of all clouds and hence more
exposed to cold than the others, are composed of
extremely fine needles of ice. Lower clouds, too, if
subjected to a sufficient degree of cold, undergo the

iSee "The Story-Book of Science."

344

SNOW 345

same transformation. Then there follows a sym-
metrical grouping of adjacent needles in delicate six-
pointed stars which, in greater or less numbers and
heaped together at random, make a sno\s^ake. Soon
afterward, when it has grown too heavy to float in
the air, the flake falls to the ground.

^^ Examine attentively one that has just fallen on
the dark background of your sleeve or cap. You
will see a mass of beautiful little starry crystals so
graceful in form, so delicate in structure, that the
most skilful fingers could never hope to make any-
thing like them. These exquisite formations, which
put to shame our poor human artistry, have never-
theless sprung from the haphazard mingling of
cloud-masses.

^'Such then is the nature of snow, the schoolboy's
favorite plaything. From a somber and silent sky it
falls softly, almost perpendicularly. The eye fol-
lows it in its fall. Above, in the gray depths, it
looks like the confused whirling of a swarm of white
insects; below it resembles a shower of down, each
flake turning round and round and reaching the
ground only after considerable hesitation. If the
snowfall continu^es thus for a little while, everything
will be hidden under a sheet of dazzling whiteness.

^ ^ Now is the time for dusting the back of a school-
mate with a well-directed snowball, which will bring
a prompt reply. Now is the time for rolling up an
immense snowball which, turning over and over and
creaking as it grows, at last becomes too large to
move even under our united efforts. On top of this
ball a similar one will be hoisted, then another still

346 THE SECRET OF EVERYDAY THINGS

smaller on that, and the whole will be shaped into a
grotesque giant having for mustache two large tur-
key feathers and for arms an old broomstick. But
look out for the hands in modeling this masterpiece !
More than one young sculptor will hasten to thrust
them, aching with cold, into his pockets. But,
though inactive himself, he will none the less give
the others plenty of advice on how to finish off the
colossus.

^ ' Oh, how glorious is a holiday when there is snow
on the ground ! If I were to let myself go, how elo-
quent I could be on the subject ! But, after all, what
could I say that would be new to you? You know
better than I all about the games appropriate to the
occasion. You belong to the present, I to the past ;
you make the snow man now and here; I only tell
about it from memory. We shall do better to go
on with our modest studies, in which I can be of some
help to you.

*^From snow to hail is a short step, both being
nothing but atmospheric vapor turned to ice by cold.
But while snow is in delicate flakes, hail takes the
form of hard pellets of ice called hailstones. These
vary greatly in size, from that of a tiny pin-head
to that of a pea, a plum, a pigeon's egg, and larger.

^*Hail often does much harm. The icy pellets,
hard as stone, in falling from the clouds gain speed
enough to make them break window-panes, bruise the
unfortunate person not under cover, and cut to pieces
in a few minutes harvests, vineyards, and fruit-
crops. It is nearly always in warm weather that hail
falls, and as necessary conditions there must be a

SNOW S47

violent storm with flashes of lightning and peals of
thunder.

*^If on the one hand a hail-storm is to be regarded
as a disaster, on the other a fall of snow is often to
be welcomed as a blessing. Snow slowly saturates
the earth with moisture that is of more lasting bene-
fit than a rainfall. It also covers the fields with a
mantle that affords protection from severe frost, so
that the young shoots from seeds recently sown re-
main green and vigorous instead of being exposed to
the deadly sting of the north wind.

*'Snow plays still another part, and a very im-
portant one, a part having to do with the very ex-
istence of our streams. On account of the cold in
high regions it snows more often on the mountains
than in the plains. In our latitude peaks three thou-
sand meters high, or more, are unvisited by rain.
Every cloud borne to them by the wind deposits, in-
stead of a shower of rain, a mantle of snow, and that
in all seasons of the year, summer as well as winter.

^'Driven by the wind or sliding down the steep
slopes, this snow from the mountain-tops, renewed
almost daily, collects in the neighboring valleys and
piles up there in drifts hundreds of meters deep,
which finally turn to ice as hard and clear as that of
the pond where we go skating. In this way there
are formed and maintained those masses of moving
ice known as glaciers, immense reservoirs of frozen
water which abound in all the larger mountain sys-
tems.

*^In its upper reaches, where the mountain peaks
pierce the sky, the glacier is continually receiving

348 THE SECRET OF EVERYDAY THINGS

fresh snow that comes sliding down the neighboring
slopes, while in its lower course, farther down the
valley, where the warmth is sufficient, the ice melts
and gives rise to a stream which is soon added to by
others from neighboring glaciers. In this way the
largest rivers are started on their courses.

^^Frbm the soil saturated with rain-water and
snow-water come springs and brooks and larger
streams, each but a slender thread at first, a few
drops trickling slowly, a tiny streamlet that one
could stop with the hand. But, collecting drop by
drop from all around, trickling down the mountain-
side, a little here and a little there, one thimbleful
added to another, one tiny streamlet uniting with
its neighbor, at last we have, first, the little brook
babbling over its smooth pebbles, then the larger
brook that drives the mill-wheel, then the stream on
which rides the rowboat, and finally the majestic
river carrying to the sea all the drainage of an im-
mense watershed.

^ ' Every drop of water that irrigates the soil comes
from the sea, and every drop returns to the sea.
The heat of the sun draws the water up in the form
of vapor ; this vapor goes to make clouds, which the
wind scatters in all directions; from these clouds
fall rain and snow ; and from this rain and snow are
formed rivers and other streams which all combine
to return to the sea the water thus distributed.

*^The water of every spring, well, fountain, lake,
pond, marsh, and ditch — all, absolutely all, even to
the tiniest mud-puddle and the moisture that bedews

SNOW 349

a sprig of moss — comes from the sea and returns to
it.

*^If water cannot run because it is held back in
the hollow of some rock, or in a depression in the
ground, or in a leaf that has drunk its fill of sap, no
matter: the great journey will be accomplished all
the same. The sun will turn it to vapor, which mil
be dissipated in the atmosphere; and, having once
started on this broad highway that leads everywhere,
sooner or later it must return to the sea.

**I hope now you are beginning to understand all
this, except one puzzling detail that must certainly
have occurred to you. You wonder how it can be
that, sea-water being so salt and so disagreeable to
drink, rain-water, snow-water, spring-water, river-
water, and so on, should be so tasteless. The answer
is easy. Recall to mind the experiment of the plate
of salt water placed in the sun. The part that dis-
appears, evaporated by the heat, is pure water and
nothing more. AVhat remains in the plate is the
salt that water contained, a substance on which evap-
oration has no hold.

*^The same process of evaporation is constantly
going on over all the broad expanse of the sea : the
water alone is reduced to vapor, the salt remains.
From this vapor, purged of all that made the sea-
water so disagreeable to the taste, only tasteless
water can result. '^

CHAPTER LXIII

ICE

0 you remember/' asked Uncle Paul, *^wliat
happened last winter to the garden pump —
that handsome red copper pump that shines so in
the sun 1 You have some idea how a pump is made.
Below there is a long lead pipe that runs down into
the well, while above is a short thick pipe in which
the piston goes up and down. This thick pipe is the
body of the pump.

^^One very frosty morning the pump was found
burst from top to bottom ; there was a crack as wide
as your finger, and out of this crack projected a strip
of ice. It caused such a commotion in the house ! It
was wash-day, and the pump would not work.
Mother Ambroisine spent all the morning fetching
water from the spring. ' '

^^I think,'' said Jules, *^they said the cold had
burst the pump ; but I racked my brains without be-
ing able to understand how cold could burst a metal
pipe. An iron or copper pipe is so hard!"

^^And then. Uncle," put in Emile, **that same
night, the night of the hard frost, I had left my pen-
holder, a small metal tube, on the bench in the gar-
den. I found it again in the morning not damaged
in the least. How had it stood the cold when the
big strong pipe of the pump had burst?"

350

ICE 351

*^That will all become clear," his uncle replied,
*4f you will listen to me."

^*We are listening with both ears, Uncle Paul,"
Emile returned, eager for the explanation.

^^It is true the cold had burst the pump, but not the
cold alone. There was something in the body of the
pump, there was — "

^' There was water," Jules hastened to interpose.

**This water, when the cold came, was turned into
ice which found itself imprisoned between the body
of the pump and the piston, without being able to
move either up or do^vn. Now, I must tell you that
ice expands as it forms. It expands so much that if
it happens to be imprisoned it pushes this way and
that, in all directions, and breaks the obstacle that
arrests its expansion. So the body of the pump
burst because ice formed inside."

^^Then the tube of my penholder was not burst
by the cold because there was no water in it?" asked
Emile.

*^ Exactly."

*^But if there had been water there which could
not get out?"

^^It would most certainly have burst."

' ' That will be a fine experiment for next winter. ' '

^'Speaking of experiments, I will tell you of one
that will show you the power of ice when it forms
and expands in an enclosed space. What is more
solid than a cannon? It is made of bronze, a metal
almost as unyielding as iron ; it weighs several hun-
dred pounds; and its cj^lindrical wall is a hand's
breadth or more thick. The cannoneer loads it with

S52 THE SECRET OF EVERYDAY THINGS

a small sack of powder and a ball that Emile would
find it hard to lift. The powder takes fire, there is
an explosion like a clap of thunder, and the iron ball
is shot to the distance of a league or even farther.
Judge then the resistance this terrible engine of war
must offer.

**Well, the expansive force of ice has been tried
on cannons. A cannon is filled with water and its
mouth stopped up with a solid iron plug screwed so
tight that it cannot move. Then the whole is ex-
posed to the cold during a severe winter day. The
water freezes and soon the cannon is split from end
to end, the ice crowding out through the cracks.
What wonder that the pipe of a pump bursts under
pressure of ice, when a cannon is rent like an old
rag ? I must tell you further that this rupture under
the pressure of freezing water is accomplished in the
quietest way. There is no explosion, as you might
imagine there would be, no scattering of flying frag-
ments in every direction. Without any noise the
metal is forced apart, and that is all. Should you
be sitting astride the cannon, you would have noth-
ing to fear when the rupture came. ' '

The children listened very attentively, being much
interested in the bursting of a cannon by something
apparently so harmless as ice. But in one partic-
ular they were left unsatisfied: they had no oppor-
tunity to test for themselves the power of ice. Their
uncle read their thoughts, and added :

^^ There is not much chance of your ever witness-
ing the bursting of a cannon by ice, and your eyes
tell me that you are waiting for me to suggest some

ICE 353

substitute. Well, then, how will this do ? Next win-
ter take a bottle, fill it full of water, and then cork
it securely with a good stopper tied down with
string. Put your bottle out of doors when there is
a sharp frost. Sooner or later you will find it in
pieces, broken by the pressure of the ice. Here
again there is no danger. The pieces of the bottle
are not sent flying all about, but remain close to-
gether, clinging to the ice; or else they fall harm-
lessly to the ground. That will be an experiment
more worth while than the one with the penholder.
Try it when winter comes. ''

'*We certainly shall," Jules responded. *^It will
be a curious sight. I have an idea. Uncle Paul; let
me tell it to you. In the new pump that was put in to
take the place of the old one when that was burst,
there is a tap at the bottom ; and when it seems likely
that there will be a hard frost Mother Ambroisine
always goes and opens the tap to let the water run
out. That must be to keep ice from forming inside
the pump?"

''Yes, that is it. Moreover, as one might forget to
open the tap, it is prudent during very cold weather
to wrap the pump with rags or straw to shelter it
from the air and prevent its getting too cold. That
is a precaution to be taken next winter."

CHAPTER LXIV

PEBBLES

WHAT might not a stone teach us if we could
only make it tell its story; or, rather, if we
could read what it offers to eyes that know how to
decipher the inscription! Perhaps some very inter-
esting facts. A pebble has so long a life ! It is as
old as the world. It has witnessed events of the re-
motest antiquity, but is a silent witness and guards
its secrets so well that we can get little clue to them
even by the most attentive study. Nevertheless let
us attempt this study.

^^We will go down to the river near by, where the
water runs over a bed of stones that are worn smooth
as if some patient marble-cutter had taken it into his
head to polish them. There are some almost as
round as balls, others oval, still others flat, some
large and some small, some short and some long,
and others that are white, ash-colored, gray, black,
or reddish. The smallest look not unlike the sugar-
plums that fill the confectioner's jars. All are re-
markable for their polished surface. Their smooth
outlines are pleasing to the touch. These water-
worn stones found in our streams are known as peb-
bles or pebble-stones.

^^Who fashioned and polished them in this man-
ner! A fragment of stone such as is broken from a

354

PEBBLES 355

rock by some chance does not look at all like this.
It is irregular, angular, rough to the touch. On the
rocky slopes of mountains are seen only stones as
shapeless as those that the road-maker leaves piled
up along the way after he has broken them. Why,
then, when under water are they always sleek and
round? The answer is not far to seek.

^*As a result of the disturbance created by storms,
by the melting of great masses of snow, and by vio-
lent freshets, the river receives a vast quantity of
loose stones that have been swept down from the
neighboring slopes. These stones are at first shape-
less, with the sharp edges and the many irregulari-
ties of stones broken by chance. Henceforth they
are under water in the bed of the river. What will
be the result? You will know if you stop to think
what would take place if a multitude of little irreg-
ular pieces of stone were shaken for a long time in a
rolling cask.

*^ Falling against one another unceasingly, clashing
together and in constant friction, these pieces would
gradually lose their sharp corners, tone down their
little roughnesses, and end by becoming perfectly
smooth. Marbles, which you prize so highly, are
rounded and polished in this way. Small pieces of
stone are first roughly shaped with a hammer, then
thrown into a rolling cask, and there the work is fin-
ished and brought to perfection.

*^ Running water plays the same part as the rolling
cask. At the season of high water the force of the
current displaces the stones lying at the bottom of
the stream and carries them away, rolling them long

356 THE SECRET OF EVERYDAY THINGS

distances. Oontinually dashed one against another,
these stones gradually become rounded, after which
the loose sand carried away with them rubs and
smooths them ; and lastly the fine mud that is washed
over them again and again imparts, by its gentle
action, the final polish. But work of this sort takes
a long time. If months do not enable the river to
fashion its pebble-stones, it will take years ; if years
are not enough, it will take centuries ; for in this mat-
ter time is of no account.

^ ^ That is how every stream, from the largest to the
smallest, strews its bed with rounded pebbles, often
in vast quantities. Running water has rolled them
along while shaping them ; it has carried them some-
times long distances, so that in order to find stones of
like nature you would have to go back to the moun-
tains where the brook or the river had its rise.
There only would be found the rock that had yielded
the fragments destined to become the pebbles of the
plain.

**What, you may ask, is the use of this history of
pebble-stones? You will see. Each of us may have
chanced to notice, far from any stream, either in a
flat country or on some hillside or even on some con-
siderable height, great piles of round, polished peb-
bles similar in every way to those rolled down by
rivers. In each instance there is the same smooth
surface, the same rounded shape like that of a ball
or an egg or a big sugar-plum or a disk. The stones
we select one by one on the river-bank in order to
make them skim along the surface of the water are
not better shaped.

PEBBLES 357

**Wliat, then, has given to these pebbles the form
they wear ? Evidently running water, for they do not
differ from the pebbles found in brooks and rivers.
Water has washed them thither, polishing them on
the way by mutual friction — the same process that
goes on in every river-bed. There is no doubt about
that: their rounded form tells the story of these
stones very plainly.

*^But to-day these piles of pebbles, covering large
tracts of land to a great depth, occupy regions that
in many instances have not even the tiniest brook-
let. Where formerly rivers ran and impetuous tor-
rents roared, there is now nothing but dry land.
The streams have all disappeared and their beds
alone remain, sometimes several leagues wide, like
those of the largest rivers of the world.

** History makes no mention of these ancient
streams. Nor can it speak of them, for it is doubt-
ful whether man ever saw them ; and if he saw them,
the centuries have effaced all remembrance of them.
Trails of pebbles are the only witnesses that tell us
where these streams once ran.

*'Now these pebble-trails often occupy steep slopes
and lofty heights that rise far above the surround-
ing plains. Never could rivers have run over such
heights. A stream must have for its bed some ra-
vine, not a ridge of hills. How, then, can we recon-
cile these two contradictory facts, that running water
has certainly been there, as proved by the multitude
of smooth pebbles still remaining, and that water
could not have reached such heights even in the
greatest floods'?

358 THE SECRET OF EVERYDAY THINGS

^^The contradiction disappears and everything is
explained when we consider that the earth's surface
is subjected to constant variation. Time works
changes in all things, even in mountains. In the
course of centuries what was once a valley may be-
come a plain, and what was a plain may rise and
form a hill. Earthquakes and the sudden uprising
of Monte Nuovo, near Naples, have already furnished
us some information on this curious subject; and
pebbles furnish us still more. They tell us that the
heights they now occupy were formerly plains or
valleys where mighty rivers ran; they bear witness
that what is now a pebbly mountain-side where one
would search in vain for the tiniest spring was in
ancient times the bed of a raging torrent ; they teach
us, in a word, that in ages long past profound up-
heavals changed the surface of the earth. Such is
the strange history that a pebble tells us when we
know how to question it. ' '

CHAPTER LXV

THE FORCE OF STEAM

TO-DAY I will show you a couple of experimentg
we used to perform for our own amusement
when I was of your age. You may like to repeat
them yourselves at the first opportunity. They will
teach you how it is that steam has become the might-
iest toiler man has ever had in his service.

^^We have seen how the vapor drawn up by the
sun^s heat forms clouds, which let fall rain and
snow, the source of all the streams that flow on our
planet. Let us try to understand by what device
man has succeeded in harnessing the steam produced
by the heating of water, so that he now commands a
servant of unlimited strength and fit for all sorts of
tasks.

' ' Take a small bottle, a vial hardly larger than an
egg, and pour into it a little water, let us say about
a spoonful; then stop the bottle with a good cork
so as to make it air-tight. After you have done this
put your bottle before the fire, on the warm ashes
and not far from the red-hot coals. Then retire
some distance, to be out of range of any possible
spattering of hot water, and await results.

^'The water heats, gives forth steam, and finally
boils. All at once there comes a pop, and up goes
the cork into the air, propelled by the thrust of the

359

S60 THE SECRET OF EVERYDAY THINGS

imprisoned steam. To make this water-pistol go off
with the best effect, the stopper must fit exactly and
let no steam escape prematurely. If allowed to es-
cape gradually as it formed, in the manner familiar
to you in the ordinary tea-kettle, the steam would
accomplish nothing whatever.

*^But the corkstopper, if it fits properly, com-
pletely closes the mouth of the bottle until the steam
has acquired sufficient volume and force to drive it
out with a sharp report. It might even offer too
great resistance, and in that case the bottle itself
would have to give way, shattered by the irresistible
pressure of the steam.

^'Therefore this experiment should be conducted
with some caution; otherwise it might cause bums
from scalding steam and wounds from broken glass.
Keep at a safe distance, then, while the water is
heating, but without allowing yourselves to be unduly
alarmed, for the danger is really very slight, in fact
almost negligible. Unless the cork be tied down it
will be almost sure to yield before the bottle itself
bursts, and there will be nothing to fear.

^*But there is still another and more convenient
method of performing the experiment, and one that
will excite no alarm even in the most timid. You
are familiar with a certain form of penholder in two
parts, one fitting into the other. Into the shorter
section the pen is inserted, while the other, which is
much longer, serves as handle and is grasped by the
fingers. It also plays the part of case or sheath,
being cylindrical in form and sheathing the pen
when not in use. Well, now, take one of these little

THE FORCE OF STEAM 361

metal cylinders and pour into it a few drops of
water ; then cut a slice of potato or carrot, making it
about as thick as your finger, and through it thrust
the open end of your penholder. The sharp, cir-
cular edge of the orifice will cut a little round plug
which will remain in the end of the holder as a
stopper. Your water-pistol is now loaded and ready
to be discharged.

^'Kold the end opposite the stopper in the flame ^
of a candle, taking care to use a pair of nippers or
a split stick of wood for the purpose, to avoid burn-
ing your fingers. Soon you will hear a noise inside
the penholder, indicating that the water is beginning
to boil and steam is forming. Then the pistol will
go off, sending the stopper to some distance, while a
jet of steam escapes from the cylinder.

*' Your little piece of artillery is soon reloaded. A
few more drops of water, another potato plug, and
there you have the gun ready for a second discharge.
In this manner you may keep up as long as you
please this miniature cannonade in which water takes
the place of gunpowder and a harmless bit of po-
tato serves as cannon-ball.

^* After performing these experiments your inquir-
ing mind will seek the cause of this power possessed
by steam. This vapor of water is seen by us rising
from drying linen with such tranquillity, such lack of
all appearance of strength, that no one pays it any
heed. From a boiling pot, again, we see it ascend-
ing as harmlessly as possible. But in the experi-

1 But first be sure that your penholder is not made of celluloid,
which is very inflammable. — Translator.

362 THE SECRET OF EVERYDAY THINGS

ments with the bottle and the penholder it shows it-
self possessed of the explosive force of gunpowder.
Whence does it derive this force ?

' * Steam may be likened to a spring which, if con-
fined in too restricted a space and pressed down upon
itself, exerts a repulsive force on obstacles oppos-
ing it, but is no sooner set free than it ceases to act.
It is thus that we may conceive of the power of
steam: free to expand at will, steam has no appre-
ciable energy ; but closely confined and receiving con-
stant additions, it becomes more and more com-
pressed and puts forth increasing efforts to escape,
until at last every bond is burst, no matter how
strong.

^'If the bottle were left uncorked and the penholder
unstopped, the steam generated in them would es-
cape freely as fast as it formed. It could not ac-
cumulate and thus become a sort of compressed
spring pushing against everything in its way. But
with the cork or the potato plug doing its part the
situation is entirely changed. Confined in too nar-
row a space, the steam accumulates until finally it
gains strength enough to hurl to a distance, and with
a loud report, the obstacle opposing it.

*^0f course it is to be understood that this pressure
of the steam is exerted not merely against the stop-
per of the bottle and the plug of the penholder; it is
exerted with equal force against all parts of the in-
terior of the bottle and of the penholder, but only
the point of least resistance yields to the pressure.
Less resistant than the glass of the bottle and the
metal of the penholder, the cork stopper and the po-

THE FORCE OF STEAM 363

tato plug give way and are projected to a distance.
If they offered sufficient resistance, the bottle and
the penholder would burst.

*^ Perhaps I have not yet made sufficiently clear to
you the power of steam pent up in a narrow space.
There is a plaything dear to youngsters of your age,
the elder-wood pop-gun, which will help to make the
matter plain. You are cleverer than I, no doubt, in
making and operating this toy. Never mind ; for the
benefit of any that may be uninformed I will describe
this famous pop-gnn and tell how it is operated.

^' First you select from the hedge a suitable piece
of elder-wood — a piece as large around as the neck
of a bottle, very straight and even, and of about a
spanks length. The elder is unusually rich in pith,
and this is easily removable; all you have to do is
to push it out with a slender stick, whereupon you
have a substantial and serviceable tube for the bar-
rel of your gun. The next thing to do is to whittle
out a ramrod with your jack-knife. This ramrod is
simply a slender piece of wood that will fit into the
tube and reach from one end to the other. In order
to make it easier to operate, one extremity of the
ramrod is left larger than the rest and serves as
handle. That finishes the outfit, and the gun is ready
to load.

**A wad of frayed tow from some old bit of cord
that is untwisting and coming to pieces is chewed
and rechewed and formed into a plug, which is then
stuck into the pop-gun and pushed through to the
farther end with the ramrod. There you have one
outlet of the tube tightly sealed, so that nothing, not

564^ THE SECRET OF EVERYDAY THINGS

even air, can pass through. A second plug of tow,
similar to the first, is next thrust into the free open-
ing. Then, resting the handle of the ramrod against
your chest, you force the rod itself into the gun-bar-
rel until, with a loud pop^ the forward plug is pro-
jected like a bullet. But projected by what?

**What was there, to begin with, in the pop-gun,
between the two plugs ? Nothing, you will doubtless
reply. Nothing visible, certainly; but invisibility
does not mean nothingness. There was air, which
we cannot see, but which is none the less real matter.
This air was confined between two substantial plugs
of tow, which allowed no passage through at either
end of the gun. At first the air occupied the entire
length of the gun-barrel, a space quite sufficient and
affording ample elbow-room.

**But now the ramrod comes into play. The rear
plug is pushed toward the forward one so that the
air between the two is compressed within an ever-
shortening canal ; and the more the space diminishes,
the more this air strives to regain its former volume,
just as a spring when pressed down tries to return
to its original position. At last the moment arrives
when the thrust of the imprisoned air ejects the for-
ward plug, the only part of the gun that can give
way.

* * So it is that steam, crowded by the heat that gen-
erates it into a space too small for it, behaves exactly
like the air forced by the ramrod into a shorter and
shorter section of tnc pop-gun. In each instance
there is the same striving for more room, the same
violent pressure against opposing obstacles.'^

CHAPTER LXVI

SOUND

'•^ /^ rVE a light blow to a wine-glass. The glass
VJ" will ring, giving forth a sound, weaker or
stronger, lower or higher, according to the quality
and size of the glass. The sound lasts but a moment,
and then ceases. Strike the glass once more and
while it is still ringing touch the rim with your fin-
ger. Instantly all is still again; not a sound from
the glass. Why does it ring when struck, and why
does it stop ringing at the touch of a finger? Be-
fore replying let us experiment with other resonant
objects.

*^A violin-string twangs on being scraped by the
bow or plucked with the finger, and while it thus
gives forth its note it is seen to vibrate rapidly. So
rapid, indeed, is its vibration that it appears to fill
the entire space between its extreme positions, with
the result that it presents a swollen appearance in
the middle, after the manner of a spindle. With
the cessation of its vibration it becomes silent. It
also falls silent immediately at the touch of a finger.

**A bell rings on being struck by its clapper, and
if observed closely the substance of the bell will be
seen to tremble in an unmistakable manner. Place
your hand on the bronze and you will experience a
disagreeable sensation almost amounting to pain,

365

366 THE SECRET OF EVERYDAY THINGS

due to the vibration of the metal. Finally, if your
hand continues to rest on the bell, the vibration will
cease and with it the sound.

*^Let us try something still more remarkable.
Take a pin by its pointed end and bring the head very
close to a ringing wine-glass or bell. You will hear
a rapid succession of little taps. Whence do they
come? From the glass or the bell-metal striking the
pin a series of quick blows as long as the ringing
continues. They come from the lively trembling of
the sonorous object.

^^It is unnecessary to cite other examples; these
three will suffice. They show us that, in order to give
forth sound, a wine-glass or a bell or a violin-string
— in short, any object whatever — must be made to
tremble or vibrate with great rapidity. The sound
is heard as long as the vibration continues, and
ceases when the vibrating object returns to a state
of rest. That explains why the wine-glass and the
violin-string stop sounding at the touch of a finger,
and why the bell will not ring if you rest your hand
against it. The finger in the one instance, the hand
in the other, stop the resonant trembling, and in so
doing arrest the sound. Motion causes the sound;
rest brings silence.

^^To this rapid motion back and forth is given the
name I have already used, vibration. An object
from which comes a sound is in vibration ; it vibrates.
Each of its backward and forward movements, too
rapid for the eye to follow, is a vibration; and the
quicker these vibrations, the higher the note

SOUND 367

sounded ; the slower they are, the lower the note. In
a word, sound is motion, and its place in the scale
measures the rapidity of that motion.

^'In order to be heard, this sound, this motion,
must reach us. The hand detects it in its own way
when, resting on the vibrating bell, it experiences
a very disagreeable thrill; the finger becomes con-
scious of it in a peculiar manner when, touching the
violin-string, it feels a ticking sensation. But how
does the ear contrive to receive the sound when it is
at a distance from the resonant object and appar-
ently in no sort of communication with it ?

*^At this point let me invite you to join me in a
sport very familiar to you all. We will take a big
stone and drop it into a calm sheet of water.
Around the place where the stone struck the water
there is instantly formed a circle, then another and
another, and so on indefinitely; and all these circles,
described about the same center and as regular as if
drawn with a pair of compasses, grow larger and
larger, in successive rings, until they die out at a
long distance from their common center, if the sheet
of water is large enough.

^*Now, do those circles really chase one another
over the water's surface as they appear to? One
would certainly think so. You remember how fast
they go, one ring after another, each in apparent
haste to catch up with its predecessor. But the pur-
sued always keep clear of the pursuers, and the dis-
tance between the rings remains the same. And so
the fact is they are not really chasing one another;

368 THE SECRET OF EVERYDAY THINGS

they are not, in fact, moving at all ; but they have that
deceptive appearance, and it will not be hard for ns
to understand why.

^^Let us drop a straw or a dry leaf upon the sur-
face of the water. When one of these concentric cir-
cles passes like a wave, the straw or leaf is lifted
up, after which the wave goes on and leaves it, and
it sinks down again, remaining exactly where it was
in the first place. Thus it is proved that the water
does not move forward at all, for if it did it would
carry with it the straw or leaf on its surface.

**What, then, are those waves? Mere palpitations
of the water as, without changing its place, it gently
rises and falls, thus producing a succession of alter-
nate billows and furrows which appear to go chas-
ing after one another. Watch a field of wheat when
the wind blows. Its surface undulates in waves that
seem to move forward although the wheat-stalks re-
main firmly rooted in the ground. Of like sort is the
apparent movement of a sheet of smooth water when
disturbed by the fall of a stone.

**The circles on the water and the undulations of
the wheat-field explain to us the nature of sound.
Every object emitting a sound is in rapid vibration,
and each of these vibrations causes a shock to the
surrounding air and produces a wave which spreads
out in all directions, immediately followed by a sec-
ond, a third, and countless others, all resulting from
as many successive vibrations.

*^In the air thus shocked by the vibrating body
there takes place exactly what we see in the sheet of
smooth water disturbed by a falling stone and in the

SOUND 369

wheat-field ruffled by the wind. Without changing
its place the air undergoes an undulatory movement
which is transmitted to great distances. In other
words, air- waves are formed which propagate them-
selves in every direction at once through the atmos-
phere, thus taking the form, not of circles, but rather
of hollow spheres, all having a common center.

''These air-waves are not visible to us, because air
itself is invisible; but they are none the less real,
just as real as waves of water and undulations of a
wheat-field. If the eye cannot see them, the ear can
hear them, for it is from them that sound comes.
Hence they are called sound-waves. The ear hears
when sound-waves reach it from any vibrating
object.^'

CHAPTER LXVII

SOUND (continued)

* * T F there were no air around us, ' ' Uncle Paul went
A. on, *^the bell, the wine-glass, and the violin-string
would vibrate to no purpose; we should hear noth-
ing, there being no sound for us to hear. Silence
would reign even where now is deafening uproar;
the lightning's flash would be followed by no thunder-
clap. Do you ask why? Because in the absence of
air sound-waves would no longer be possible and the
ear would receive nothing to convey the sense of
sound. If you wish for a proof that silence follows
when air is removed, I will give you one.

**In the middle of a hollow glass globe of consider-
able size is hung a small bell. By means of a stop-
cock communication with the interior of the glass re-
ceptacle may be suspended or reestablished at will.
At first it is full of air, as is naturally the case with
any vessel that we call empty. If we shake it so as
to disturb the bell, we hear the latter ring, the en-
closed air transmitting the sound-waves beyond the
confines of the glass chamber; and this is true even
though the stop-cock be closed, because the undula-
tory movement of the inner air is transmitted
through the glass and into the outer air.

* ^ Now let us exhaust the air within by means of an
air-pump. To describe this pump would take us too

370

SOUND S71

far out of our way and would involve details too dif-
ficult for your comprehension. Let us pass on, then,
and suppose the glass globe emptied of all the air
it at first contained, and the stop-cock closed to pre-
vent the entrance of any air from without.

**In that condition the globe may be shaken as
much as we choose and, though we see the bell swing-
ing and its clapper beating the metal, there comes to
our ears no sound whatever. The bell does actually
move and is struck by the tongue — that is indisput-
able— but its vibrations are mute because they start
no sound-waves for lack of air. Now we open the
stop-cock, and the outer air rushes in and fills the
globe, whereupon the bell is heard as in the begin-
ning. The fact is established that with air there is
sound ; without air, silence.

^'Let us return for a moment to the concentric cir-
cles formed on the surface of a sheet of water by the
falling of a stone. These circles, these waves, are
seen to make their way far out from the center, and
their rate of progress is slow enough to admit of
being followed by the eye. If we wished, we could,
with a little care and by the help of a watch having
a second-hand,- ascertain the time consumed by one
of these waves in going from any given point to any
other, and thus the distance covered in one second.
Sound-waves are transmitted in a similar manner,
and so we say that sound travels. How far does it
travel in a second? That would be something worth
finding out. Let us look into the matter a little.

**You are standing, we will say, in full view of a
belfry some distance off. You see the bell swing and

Sn THE SECRET OF EVERYDAY THINGS

even make out the clapper as it strikes the metal.
When it strikes you know that it makes a sound, and
yet you hear nothing immediately. The sound
reaches you a little later, when the bell is swinging
back for another blow from the clapper. How is it
that the eye sees before the ear hears ?

^'The message to the eye is transmitted by light,
that to the ear by sound-waves. Now, light travels
with inconceivable speed, and for it the greatest ter-
restrial distances are as nothing. Its rapidity of
movement is comparable with that of electricity
along a wire. We see, then, the clapper striking the
bell at the very instant of the concussion, for light
no sooner starts on its journey than it arrives at its
destination.

*^But with sound-waves it is a very different mat-
ter. They travel faster than the circular ripples on
water, but still they take an appreciable length of
time in reaching us. Hence they are behindhand
from the moment the clapper strikes the bell, and
they fall more and more behind the farther they have
to go.

^^You watch from a distance a hunter about to
shoot at a bird. All attention, you wait for the dis-
charge with the lively interest felt by those of your
age in the fall of the tiniest chaffinch from its perch.
The shot is fired, you see both the flash and the
smoke, but the report does not reach you until a little
later. The explanation is the same as in the case of
the bell. Light, moving with unparalleled rapidity,
shows us the flash and the smoke as soon as the dis-
charge takes place, whereas the sound-waves, which

SOUND 373

are relatively slow of movement, bring us only later
the report of the huntsman's fowling-piece.

^^Let us suppose exactly one second to intervene
between our seeing the flash caused by the explosion
of the gunpowder and our hearing the report. Then,
if our distance from the hunter be carefully meas-
ured, it will be found to be three hundred and forty
meters. Accordingly, it has taken sound one second
to travel that distance. By similar experiments it
has been ascertained that all sound, whether loud or
subdued, shrill or the reverse, caused in one way or
in another, travels through the air at the same in-
variable rate of speed, three hundred and forty
meters per second.

^'At this point it may be interesting to make a
practical application of what we have just learned.
Suppose we wish to know how far away are the light-
ning and thunder we have just seen and heard. If
the flash of lightning and the peal of thunder reach
us at the same time, the electric discharge was very
near, since the sound, despite its relatively low rate
of speed, shows no such tardiness in reaching us as it
would have done had it come a long distance. But
usually the thunder follows the lightning after an
appreciable interval, indicating that the electric dis-
charge is not very near.

* ^ To ascertain just how near or how far away the
lightning is, we simply have to know how many sec-
onds elapse between the flash and the first thunder-
clap. If we have no watch by which to count the
seconds — as, if we are school-children, it is more than
likely we shall not have — let us simply count 'One,

374 THE SECRET OF EVERYDAY THINGS

two, three, four,' and so on, without haste, but also
without lagging. In that way we shall be able to
measure the time accurately enough.

^^Now, then, attention! Watch the storm-cloud
yonder. There comes a flash of lightning, and we
count : one, two, three, and so on up to twelve. Ha !
the thunder at last. Twelve seconds passed between
flash and report, and so it must have taken that
length of time for the sound to reach us. The point
where the discharge took place is therefore distant
from us twelve times three hundred and forty meters,
or about four kilometers. What do you say? Is n't
that simple enough? How easy it is with a little in-
telligence, to solve problems that at first seemed ex-
tremely perplexing ! To find out how far away the
thunder is we only have to count one, two, three, and
so on.

^ * The circular waves on the water have something
else very interesting to tell us. Let us go back to
them once more. The sheet of water, an enclosed
basin let us say, is bounded by a wall that serves to
hold the water in. Watch closely what takes place
where water and wall come in contact. The ripples
produced by the fall of a stone make their way to-
ward the wall in ever- widening circles, and reach the
wall one after another. Then, as soon as they touch
the wall, they start back again; always preserving
their circular form and their fixed distance from one
another, they move now in the opposite direction.

**Thus the surface of the water becomes ruffled
with two series of waves, one moving toward the
wall, the other away from it ; £tnd these waves, travel-

SOUND 375

ing in contrary directions, meet and pass one an-
other with no confusion or hindrance whatever. To
designate this change of direction we say that the
waves are reflected by the wall. Those moving to-
ward it are direct waves ; those returning from it are
reflected waves.

*^ Confronted by a wall, a rock, or any other ob-
stacle barring their passage, sound-waves behave ex-
actly like water-waves : they are reflected by the ob-
stacle and go back in the opposite direction. Hence
it is that we may hear the same sound twice in the
same place, with an interval between the first and
second hearing. The first is caused by direct waves,
the second by reflected waves. When the sound
reaches us the second time, we call it an echo.

^ ' In future when you hear your own voice from a
distance as if some mischievous sprite were mocking
you, you will know that the repetition is produced
by some opposing object, some wall or rock or other
obstruction, that sends back the sound-waves to you
by reflecting them. You first received the sound-
waves made by your voice directly, and then you re-
ceived the sound-waves reflected to you by the ob-
structing object/'

CHAPTER LXYin

LIGHT

LANGUAGE, which is older than science, abounds
in expressions whose precise meaning does not
always conform with reality. People spoke before
observing, and the word sanctioned by usage has
sometimes been found untrue in the light of subse-
quent scientific research. For example, we speak
of darting a glance at a person or object, to signify
a quick look at that person or object.

^^As a matter of fact, when we look at anything
do we send forth visual rays from our eyes to procure
for us information concerning the thing looked at?
Does that which makes us see go out from our eye-
balls? Certain terms in common use might imply
as much ; but to take these terms literally would be a
serious mistake.

^^In the act of looking nothing goes out from our
eyes ; on the contrary, all that we see comes to them
from the thing seen. Our eyeballs do not send out
anything ; they receive. We do not dart our glances
or looks, but direct them toward the objects we wish
to examine ; that is, we open our eyes and turn them
toward these objects in order to receive that which
shows them to us.

* ^ And what do we thus receive ? We receive light
which, coming from the thing seen, gives us knowl-

376

LIGHT 377

edge of it by penetrating to the interior of the eye.
The gate by which this light-message enters is the
orifice to be seen in the front of the eyeball in the
shape of a round black spot. It is called the pupil.

^^ Light tells us about distant objects somewhat as
heat announces the presence of a fire and as sound
calls attention to the tinkling bell or the booming
cannon. The heat comes from the fire and not from
us ; the sound comes from the bell or the cannon, not
from us. Light, which enables us to see, comes from
what is seen and not from us.

** Again, we speak of 'palpable darkness,' meaning
profound obscurity. The adjective palpable is ap-
plied to anything perceptible to the sense of touch.
Strictly speaking, air, although a very tenuous sub-
stance, is in reality palpable because one needs only
to wave the hand in order to feel its contact, gentle
as a light breeze. Mist and fog, which are great
masses of vapor, might still more fittingly be called
palpable. But can this be said of darkness? Can it
be likened to a sort of fog that hides things from us
by becoming thick and reveals them again by becom-
ing thin?*- Is it a material substance, a substance
that can be f^lt, and one that shuts us in like a black
veil?

''No, darkness is never palpable; it does not
thicken like fog, for it is nothing, absolutely nothing
but the absence of light. It has no existence of its
own; when darkness descends, nothing really falls
from the sky, but rather light has been taken away.
Darkness is to light what silence is to sound.

^' Sound is a very real thing with its aerial waves

378 THE SECRET OF EVERYDAY THINGS

that travel from the sonorous body to our ears.
Light also is a real thing. With incomparable speed
it travels from the luminous object to our eyes. Let
the sonorous body cease to vibrate, the luminous ob-
ject cease to shine, and in the one case we have
silence, in the other darkness ; in short, two negative
quantities.

**Any object, to be visible, must give out light. If
it does not, it is by that very fact invisible, however
perfect the eye may be. In the same way, a bell that
does not ring cannot be heard, no matter how keen
the sense of hearing. No light, no vision possible;
no sound-waves, no hearing possible.

**It is said, however, that certain animals — the cat
in particular — are able to see in complete darkness.
If that is your opinion, undeceive yourselves ; no ani-
mal can see when light is entirely wanting.

*^The cat, it is true, has the advantage of us: its
large eyes, the pupils of which can contract and al-
most close when exposed to light of dazzling bril-
liancy, or enlarge to receive more abundantly the
dim light of dark places — its large eyes, I say, enable
it to find its way where to duller vision all is utter
darkness.

*^But in reality there is only partial darkness
where the cat finds the little light it needs. If light
were entirely wanting the animal would open its big
eyes in vain ; it would see nothing at all, absolutely
nothing ; and to find the way about it would have to
depend on the long hairs of its mustache, just as the
blind man depends on his stick.

** Would you like to see how the c^t contrives to

LIGHT 379

regulate the admission of light into its eyes! Watch
it in the sun. You will see the pupil reduced to a
narrow slit like a black line. In order not to be daz-
zled by the blinding glare, the animal has nearly
closed the passage to the light; it has nearly closed
the pupil while leaving the eyelids wide open. Take
the cat into the shade. The slit of both eyes en-
larges and becomes an oval. Put it in semi-darkness
and the oval dilates until it becomes almost a circle ;
and the dilation increases as the light gets dimmer.

^* Thanks to its pupils, which open wide and can
thus still receive a little light where to others the
darkness is complete, the cat can find its way in the
dark and hunt by night still better than by day, as it
is then invisible to the mice while it sees them well
enough.

* ^ Iron heated white-hot to be hammered on the an-
vil lights up the blacksmith's dark shop. The flame
of the lamp lights the interior of our dwellings at
night. Any substance, if heated sufficiently, be-
comes, like the white-hot iron and the lamp-flame, a
source of light. The sun is the world's torch, the
radiant furnace that gives light, heat, and animation
to everything, that has life.

**It is a ball of fire about a million and a half times
as large as the earth. Its enormous distance from
us — more than thirty millions of leagues — reduces it
in our eyes to a disk only a couple of spans across;
for the more distant an object is the smaller it ap-
pears. Small as its remoteness makes it appear,
nevertheless it remains for us the undisputed king
of the heavens. Whoever should try to look it in

380 THE SECRET OF EVERYDAY THINGS

the face would immediately be dazzled and compelled
to lower his eyelids.

*^The stars, countless in number, are so many
suns, comparable with ours in brightness and size;
but their distance from us is so prodigious that these
colossal stars look like mere points of light. In-
deed, the greater number of them are not even visi-
ble without the aid of a good telescope. These dis-
tant suns light other worlds and take hardly any part
in the earth's illumination.

'^Our sun is the only dispenser of light to our
world. To its rays we owe our day; their with-
drawal causes our night.

*^ Illumined by the sun, objects send back or reflect
in all directions the light that reaches them, some-
what as a wall or rock reflects the aerial waves that
constitute sound. Reaching our eyes, this reflected
light causes us to see what surrounds us ; it is a sort
of luminous echo comparable with the sonorous echo.
The illuminated object thus becomes itself a source
of light, but of a borrowed light having its true origin
elsewhere.

**We have in the heavens above us a splendid ex-
ample of this borrowed light. The moon has no
light of its own. It is a dark body which becomes
bright by reflecting the light from the sun. Its half
that faces the sun is bright, the other dark. Accord-
ing to the relative positions of earth, sun, and moon,
the last named turns toward us at certain times the
whole of its bright half, and then the moon is full;
later only a part of this half, which shows us the
moon in the shape of a crescent ; finally the half that

LIGHT 381

does not get the rays of the sun, and for the time
being the moon is invisible although still present in
our sky. If it shone by its own light the moon would
not have these changing aspects, but would always
appear to us as does the sun, in an invariably round
and luminous form.

<< Every object that arrests light casts a shadow.
Hold your hand before the lamp when it is lighted
in the evening. On the opposite wall you will see a
dark shape, the shadow of your hand. In like man-
ner, when the sun shines, the shadow of a tree, wall,
or house can be seen on the ground. What, then, is
shadow? It is the space left untouched by light, the
latter being intercepted by some obstruction.

^* Under the cover of a tree, at the foot of a wall,
in the shelter of a rock, the direct rays of the sun
are cut off; but the light reflected by neighboring ob-
jects, themselves lighted directly, always penetrates
there. Hence we have an intermediate state between
broad daylight and total darkness, a semi-obscurity
which would be total darkness were it not for the
light reflected by neighboring objects on which the
sun shines. It is partial darkness. Where there is
no light, either direct or reflected, we have black
night/'

THE END

Internet Archive Audio

Featured

Top

Images

Featured

Top

Software

Featured

Top

Texts

Featured

Top

Video

Featured

Top

Mobile Apps

Browser Extensions

Archive-It Subscription

Save Page Now

Full text of "The secret of everyday things; informal talks with the children"

See other formats